You are right that standard ratings here are really unreliable. People have really crazy standard ratings which say little about their actual skill level. So my guess 2100-2300 is, indeed, not very accurate...Blitz is the only rating here that comes close to someone's chess skill.
Your statement ("At the level of play that the OP is curious about, both the blitz and standard ratings on this website should be very close to the player's actual FIDE rating. 2K blitz or 2K standard ~ 2K FIDE.") doesn't make any sense. 90% of all players here have a Blitz rating that is 400 points below their standard rating. Including you!
What are you talking about? I never said anything about standard rating here being highly unreliable. I believe the exact opposite. As for lower rated players such as myself having higher standard than blitz ratings, that is true. At the higher levels, it isn't.
Believing in the reliability of standard ratings here, is like convincing yourself that you are actually a decent chess player...
Who are good at blitz also good at OTB. All the masters can play blitz very well.
Only weak players play blitz. Serious players dont waste time with such silly things.
Sure, here are some of those patzers:
https://www.youtube.com/watch?v=V4IeJNYlzWs
https://www.youtube.com/watch?v=0749jCB2IQ8