I personally would rather they be able to keep their accounts open instead of starting new ones. I have some control over who can buy when they keep their old accounts, but none if they keep opening new accounts. If they're blocked from buying from all sellers there's no doubt in my mind they'd all open new accounts, and they may be resentful enough to play even more games.
Don't assume they start with a clean slate after 12 months - it's only the oldest strikes that drop off the list and I suspect most who do it have plenty more in the pipeline to still ensure they can't buy from anyone with blocks in place.
My newbies are all good and I have absolutely no problems with them. I have quite a lot of them buy and I don't require phone verification. The only low feedback people I have trouble with are those who've been members for years and rarely buy, but I only strike them once or twice a year. Most of the people who've been blocked for too many strikes have feedback of at least 400, and most are way higher than this.
