I've made many new accounts over the last 10 years. I never had a problem getting my rating to where it should be.
Not to mention it's impossible for 75% of players in a large bracket like that to be underrated. You can't reasonably make the argument they all purposefully offset it by resigning because this is 100s of thousands or millions of players.
Notice too that you can't reasonably make the argument that they just close their accounts and reopen because 800-1200 is high population band, meaning your argument is essentially that the "real" rating curve should have a large depression in the 800-1200 band instead of what it is now (similar to a bell curve).
Disclaimer: I have not broken any chess.com guidelines, I closed my previous account a couple months before making this one. This is the only chess.com account I currently own.
Smurfing: act of a high-skilled gamer playing within a lower-level character or competitive bracket
Source: Wikipedia
For those stuck in the 800, 900, 1000, even 1200 rated brackets, do not worry! The people in this range are not the same rated as you. In other words, they are also smurfing. 75% of the opponents I've versed here play way too well to be low rated. These people are hindering you from growing.