It is impossible for anyone to provide a reasonable answer on why you got downvoted, or why you think you answered correctly. However, irrespective of the questions you linked, this is a generic answer.
What difference does it make how many downvoted your answer or why? Only you — and Allah ﷻ — will know your intention. If your intention is to spread your knowledge for the sake of Allah alone, then your reward will come from Allah, and it matters not how many downvotes your answers get. If your intention is to gain a reputation for this world, then revisit your actions as you may be entering a very dangerous area:
حَدَّثَنَا يَحْيَى بْنُ حَبِيبٍ الْحَارِثِيُّ، حَدَّثَنَا خَالِدُ بْنُ الْحَارِثِ، حَدَّثَنَا ابْنُ جُرَيْجٍ، حَدَّثَنِي يُونُسُ بْنُ يُوسُفَ، عَنْ سُلَيْمَانَ بْنِ يَسَارٍ، قَالَ تَفَرَّقَ النَّاسُ عَنْ أَبِي هُرَيْرَةَ، فَقَالَ لَهُ نَاتِلُ أَهْلِ الشَّامِ أَيُّهَا الشَّيْخُ حَدِّثْنَا حَدِيثًا سَمِعْتَهُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ نَعَمْ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " إِنَّ أَوَّلَ النَّاسِ يُقْضَى يَوْمَ الْقِيَامَةِ عَلَيْهِ رَجُلٌ اسْتُشْهِدَ فَأُتِيَ بِهِ فَعَرَّفَهُ نِعَمَهُ فَعَرَفَهَا قَالَ فَمَا عَمِلْتَ فِيهَا قَالَ قَاتَلْتُ فِيكَ حَتَّى اسْتُشْهِدْتُ . قَالَ كَذَبْتَ وَلَكِنَّكَ قَاتَلْتَ لأَنْ يُقَالَ جَرِيءٌ . فَقَدْ قِيلَ . ثُمَّ أُمِرَ بِهِ فَسُحِبَ عَلَى وَجْهِهِ حَتَّى أُلْقِيَ فِي النَّارِ وَرَجُلٌ تَعَلَّمَ الْعِلْمَ وَعَلَّمَهُ وَقَرَأَ الْقُرْآنَ فَأُتِيَ بِهِ فَعَرَّفَهُ نِعَمَهُ فَعَرَفَهَا قَالَ فَمَا عَمِلْتَ فِيهَا قَالَ تَعَلَّمْتُ الْعِلْمَ وَعَلَّمْتُهُ وَقَرَأْتُ فِيكَ الْقُرْآنَ . قَالَ كَذَبْتَ وَلَكِنَّكَ تَعَلَّمْتَ الْعِلْمَ لِيُقَالَ عَالِمٌ . وَقَرَأْتَ الْقُرْآنَ لِيُقَالَ هُوَ قَارِئٌ . فَقَدْ قِيلَ ثُمَّ أُمِرَ بِهِ فَسُحِبَ عَلَى وَجْهِهِ حَتَّى أُلْقِيَ فِي النَّارِ . وَرَجُلٌ وَسَّعَ اللَّهُ عَلَيْهِ وَأَعْطَاهُ مِنْ أَصْنَافِ الْمَالِ كُلِّهِ فَأُتِيَ بِهِ فَعَرَّفَهُ نِعَمَهُ فَعَرَفَهَا قَالَ فَمَا عَمِلْتَ فِيهَا قَالَ مَا تَرَكْتُ مِنْ سَبِيلٍ تُحِبُّ أَنْ يُنْفَقَ فِيهَا إِلاَّ أَنْفَقْتُ فِيهَا لَكَ قَالَ كَذَبْتَ وَلَكِنَّكَ فَعَلْتَ لِيُقَالَ هُوَ جَوَادٌ . فَقَدْ قِيلَ ثُمَّ أُمِرَ بِهِ فَسُحِبَ عَلَى وَجْهِهِ ثُمَّ أُلْقِيَ فِي النَّارِ " .
It has been narrated on the authority of Sulaiman b. Yasar who said: People dispersed from around Abu Huraira, and Natil, who was from the Syrians. said to him: O Shaikh, relate (to us) a tradition you have heard from the Messenger of Allah (ﷺ). He said: Yes. I heard the Messenger of Allah (ﷺ) say: The first of men (whose case) will be decided on the Day of Judgment will be a man who died as a martyr. He shall be brought (before the Judgment Seat). Allah will make him recount His blessings (i. e. the blessings which He had bestowed upon him) and he will recount them (and admit having enjoyed them in his life). (Then) will Allah say: What did you do (to requite these blessings)? He will say: I fought for Thee until I died as a martyr. Allah will say: You have told a lie. You fought that you might be called a" brave warrior". And you were called so. (Then) orders will be passed against him and he will be dragged with his face downward and cast into Hell. Then will be brought forward a man who acquired knowledge and imparted it (to others) and recited the Qur'an. He will be brought And Allah will make him recount His blessings and he will recount them (and admit having enjoyed them in his lifetime). Then will Allah ask: What did you do (to requite these blessings)? He will say: I acquired knowledge and disseminated it and recited the Qur'an seeking Thy pleasure. Allah will say: You have told a lie. You acquired knowledge so that you might be called" a scholar," and you recited the Qur'an so that it might be said:" He is a Qari" and such has been said. Then orders will be passed against him and he shall be dragged with his face downward and cast into the Fire. Then will be brought a man whom Allah had made abundantly rich and had granted every kind of wealth. He will be brought and Allah will make him recount His blessings and he will recount them and (admit having enjoyed them in his lifetime). Allah will (then) ask: What have you done (to requite these blessings)? He will say: I spent money on every cause in which Thou wished that it should be spent. Allah will say: You are lying. You did (so) that it might be said about (You):" He is a generous fellow" and so it was said. Then will Allah pass orders and he will be dragged with his face downward and thrown into Hell.
— Sahih Muslim, Book 33, Hadith 218
From the hadith above, one of the first three that will ignite hellfire on Judgment Day is someone who spreads knowledge (correct knowledge, mind you) for the sake of being called knowledgeable.
Once the intention is in the right place, the second most important tool is the right knowledge. One has to be extremely careful when inviting to the path of Allah, that one does so with knowledge and insight:
قُلْ هَٰذِهِ سَبِيلِي أَدْعُو إِلَى اللَّهِ عَلَىٰ بَصِيرَةٍ أَنَا وَمَنِ اتَّبَعَنِي ۖ وَسُبْحَانَ اللَّهِ وَمَا أَنَا مِنَ الْمُشْرِكِينَ
Say, "This is my way; I invite to Allah with insight, I and those who follow me. And exalted is Allah; and I am not of those who associate others with Him."
— Surat Yusuf 12:108
One has to always remember that answering without knowledge is a work of the Shaytān:
يَا أَيُّهَا النَّاسُ كُلُوا مِمَّا فِي الْأَرْضِ حَلَالًا طَيِّبًا وَلَا تَتَّبِعُوا خُطُوَاتِ الشَّيْطَانِ إِنَّهُ لَكُمْ عَدُوٌّ مُّبِينٌ. إِنَّمَا يَأْمُرُكُم بِالسُّوءِ وَالْفَحْشَاءِ وَأَن تَقُولُوا عَلَى اللَّهِ مَا لَا تَعْلَمُونَ
O mankind, eat from whatever is on earth [that is] lawful and good and do not follow the footsteps of Satan. Indeed, he is to you a clear enemy. He only orders you to evil and immorality and to say about Allah what you do not know.
— Surat Al-Baqarah 2:168-169
This goes to the extent that Allah ranks doing so high up among the forbidden:
قُلْ إِنَّمَا حَرَّمَ رَبِّيَ الْفَوَاحِشَ مَا ظَهَرَ مِنْهَا وَمَا بَطَنَ وَالْإِثْمَ وَالْبَغْيَ بِغَيْرِ الْحَقِّ وَأَن تُشْرِكُوا بِاللَّهِ مَا لَمْ يُنَزِّلْ بِهِ سُلْطَانًا وَأَن تَقُولُوا عَلَى اللَّهِ مَا لَا تَعْلَمُونَ
Say, "My Lord has only forbidden immoralities — what is apparent of them and what is concealed — and sin, and oppression without right, and that you associate with Allah that for which He has not sent down authority, and that you say about Allah that which you do not know."
— Surat Al-A'raf 7:33
May Allah guide us all to His right path.