No one can be 100% trustworthy. I have seen vendors in Localbitcoins selling their old accounts to scammers and the latter using them to con unsuspecting users.
Bingo! I see that happen even here on non crypto marketplace sites. The first sign of trust (people think like that) is to avoid new accounts and only deal with older accounts---resulting in scammer offering big money for these older accounts.
People with older accounts who don't often list anything for sale will likely not reject an offer of a few hundred bucks for their account, especially since they can simply create a new one.
It provides scammers easy access to old accounts. By the time people no longer connect trustworthiness to old accounts, scammers will find other routes to gain people's trust and scam them. They are always a step ahead.