Whats going on here?

For the last couple years my daily correspondence chess rating on chess.com has been sub 1100 and my blitz and bullet ratings are not even worth mentioning. I have always felt like I wasn't improving even though I learn more every day. I'm watching chess videos, reading my books, and practicing tactics every day.  I decided for the heck of it i would go elsewhere just to see if I would have better luck.

Out of 10 15+15 games I have won 6. All of them in the 1100 to 1400 Range.

I felt like i was playing really well and was excited to see my rating at almost 1400. But at the same time I'm not sure if this is true. There shouldn't be that much of a difference between websites right? Maybe my daily chess opponents are cheating? Or i just got lucky.

my classical rating elsewhere is 1600 where I play 30/30
my chess.com rapid is 1200: here i play 30 and i am frequently losing on time

my coach has said that chess.com ratings from 1200-1400ish might be deflated (unlike many who say the opposite)

i have played many players on chess.com who have 1200 ratings and play every bit tough as many players 1400+ otb at my chess club

i get good games on both sites but if i am really looking for “otb practice” i will play 45/45 on another site since it takes a really long time to get a game on chess.com

You can't compare ratings between sites. On chess.com if you don't know a thing about chess, you'll probably be rated 100, while other places have a minimum of 800. Another site has 1500 as average/the starting point while here if you're 1500 you're better than around 80 percent of players.