It's input delay. You can dress it up with any term you want but it's input delay. Was jiggle peeking such a problem that people would rather control their characters with puppet strings? Anything to sell the fantasy of LARPing as a tacticool combatant I guess.
In my opinion there are going to be far more players turned off by the movement than there would be people quitting because they got jiggle peeked. Maybe I'm wrong. I'm not complaining that the playstyle was nerfed but I think the way they did it was a bit heavy handed and could be more targeted at the jiggle peek itself instead of movement as a whole.
Edit: I sucked before the update and I've probably done better since the patch. I'm not the jiggle peeking chad you all seem to think I was. I'm just a shitter that enjoys FPS games when they feel great to move and shoot.
Source: https://www.reddit.com/r/EscapefromTarkov/comments/rha6td/inertia_update_honeymoon_phase/