Yeah I can't tell you how many Twitter/X profiles say 'this is my [xth] account' or some variation thereof. I think the record I have personally seen is '18th' or '19th' (today I blocked someone who's profile stated they were on Try # 14)
Most people just launch another burner email (I don't think they're checking IP addresses or SIMS, at least not in the USA)
I think there's something like rate limiting going on for Twitter/X DMs & if you fire off too many similar / identical DMs in too short a period of time, that gets you suspended.
Also I'd add a fifth lesson to your list
5) Request an archive of your Twitter/X account on a regular basis (at least monthly, maybe more often) while that's still possible to do