We have had this with one of our sons. Lockdown completely exacerbated it. He spent all of this time gaming as there was nothing else to do, his room was disgusting and he was belligerent and rude to the rest of us. He dropped out of uni as It was all virtual so he didn't see the point in us spending the money (and it meant he couldn't stay up all night gaming with his "Friends"). He had endless political and social opinions that ultimately always seemed to be excuses why he couldn't do anything else.
In the end, we pulled the rug out from under him. It sounds brutal but I decided that I had to treat the suicide threats as just that, threats, because he refused treatment and refused to see a counselor as he "didn't see the point". We were lucky that we could financially take a hit so we found him a flat, paid the deposit and the first 4 months rent. Told him if he wanted to go back to Uni, we'd keep paying the full rent. If he didn't (and he didn't), he needed to find a job or alternative and we would only help financially if he was actively trying to stand on his own two feet.
He's now what I privately think of as a work in progress. He has a full time job and, although he doesn't earn enough to fully cover the rent, as long as he keeps at it, we happily make the difference. He stands taller, he laughs more, he's clean(!), he socializes outside of the gaming world again. He comes home for dinner once a week (that's all on him, I would not be offended in the slightest if he didn't). I am so incredibly proud of him and, although he still has a way to go before he's a fully independent adult, he is 10000% closer to it now than he was a year ago.
And yes, I blame myself for him ending up there in the first place and I cannot remember how many nights I lay awake terrified that one day, he'd prove his threats weren't just manipulation but true. I love that kid with all of my heart, even when he was an absolute arsehole. I do think the gaming community has a part to play as there is this huge global community of particularly young men who feel exactly the same as my son did and they, I dunno, egg each other on is the wrong phrase. Maybe just validate each other that their lives are not their faults and the whole world is against them improving them. And then that just becomes their truth.
Well, THAT was quite a ramble!