Chamber nerf doesn't mean anything

I don't think the Chamber nerfs are going to affect his pick rate considering that the other sentinels are very weak.
Killjoy is utterly useless on maps with a Breach and with the Kay/0 buffs his nade can destroy the KJ ult through the wall. This puts her viability on maps like Ascent, Haven and Icebox in doubt.
Cypher on the other hand is useful only on Breeze and maybe Split but Raze exists. Unless you have a really good Cypher who has proper setups I doubt you can really find value with him as his ultimate doesn't do much.
Unless Riot introduces a balance patch for the sentinels like they did for all the controllers, I think Chamber is still going to be the number 1 picked agent.

it does mean something. but not to the rate people are making. Just like JETT predash nerf, no other nerfs change much but the tp. It just gave opponents a chance thats all.