Cannot connect after character select

I've tried for several years to return to this game, and every time, I've been plagued with the exact same bug: more often than not, the game client doesn't open after character select. I'm presented with a launcher screen and a reconnect button that does absolutely nothing. Clicking reconnect does nothing. It's worthless. It has no function whatsoever. Despite years of bug reports on this exact same problem, I have yet to see a real solution from Riot Games or any indication that the company is truly aware that this is a persistent problem and not something that can be solved with the standard troubleshooting that are occasionally presented in threads about the issue.

I would like to play the game again. I spent quite a bit of money on my account. I would like to use it without having to run afoul of Leaverbuster simply because the client has decided not to work one night despite working just fine on others.

I've reinstalled. I've run the Hextech tool. I've disabled antivirus. I do not use a firewall beyond Windows Defender. None of this works. None of it at all.

Please spend some of the money you've reaped from this game over the past ten years and fix it so that it can actually be played.