You do realise that part of the game is retaking. Like it or not, you will have to retake. Better to retake as a team than to die solo because you thought you were playing old Chamber where you can just hold a site by yourself with an operator.
The suppress is pretty useful and it is literally intended to open space and punish people who might hold a tight angle or off angle.
As for your complaint that "Iso's util does not have an easy counter" - his shield is literally breakable with 1HP of damage. You can blind shot a molly or shock dart or anything else which damages and it breaks his shield nullifying it's utility until he gets a kill - which by the way is a lot harder without his shield tanking a hit.
You complain that Iso counters how Chamber plays and you're mostly right. However, you can still take that early aggression with a teammate. You have to make more conscious decisions throughout the match rather than depend on your agent alone to hold a site. Remember, Valorant is a team game. You have to pick and pull apart your opponents to get the best results.
You complain that your pocket pick has a counter - why not try different agents at the same time. You are not meant to have one instalock and expect to win every game. And even if you still think you can play one instalock, you should embrace the challenge of playing against a hard counter like Iso.