@Nikhil3 Brother
Frankly Speaking I have not noticed too much Reduced or any Pixalation Issues on GSat 10 TP Channels.
But after Shifting Large Number of HD & SD channels in GSat - 10 may be TS Backend Team have gone with Video Compression and that in too extent it can hamper the PQ in a way.
As I have Subscribed most of HD Channels and Watch Less SD Channels but for Me SD Channels (whichever I watch) PQ have not downgraded so far.
May be I am in use of HEVC STB so it's not issue for me.
According to GSat 10 K10 TP - May be excess Shifting of Channels in a row can create these. But as You say that this Issue is undergoing for Last 2 Years that's Surprised Me a Lot. Because I have not seen any Experts of DDF - TS Forum have raised or created any thread on that. So Now I have also doubt.
On GSat 10 K10 TP - I have searched and checked for You :- CNN / Al Jajeera / India Ahead just now. It's fine for Me. Only DD India I saw some Pixalation issue. B4U Kadak & Abzy Movie are working average. Cinema TV is Fine.
For Me as Bangla Viewers :- on GSat 10 K10 (as You suggested) there is a little issue on Zee 24 Ghanta SD & Rupashi Bangla SD. But News 18 Bangla & Music F working Fine for me.
May be You are finding these issues on Matribhumi News / M.Manorama / Flowers / Janam TV etc. But I have not subscribed to these so cannot Comment.
May other Experts or Mates reading this can Put a Light on it.