The answer is very simple. Full chess streaming does nothing to improve your chess.
For players under 2200 (which I don't think any of these players are) the single best thing to do is work on tactics.
For players over 2200 the best thing to do is what this answer to a similar question says:
The principle teaching of the Soviet School of chess as described by Dvoretsky and others is that the key to improvement lies in annotating your own games.
Only by critically examining the (bad) moves you make can you identify the kind of mistakes you typically make and only then can you take positive steps to correct them.
This is a very active thing to do. It involves putting your brain into gear. Just putting your game into an engine and seeing where the evaluation changes by a big margin and noting the engine suggestion doesn't count. That is just passive.
If you are "full-time chess streaming" you are not spending much time doing deep analysis of your own games and mistakes. You are not doing what is necessary for improvement. Instead you are presenting shallow chess for entertainment and money.