Email sending is a largely efficient market, and SES is the cheapest sender. Thus, the SES IP pools have the worst IP reputations among all the SMTP-based senders. I would never use them (or an ESP that sends with them) in a million years. The reason why cheap = bad in email is because Spammers have the lowest conversion rates of all senders (their emails are always untargeted), so price is their number 1 considerati…
You are assuming that SES allows for spammers. In my experience, SES has pretty good controls , limits and policies to dissuade from spamming.
The cheapest service will always get the most attempts from spammers. You can try to detect them before they send, but the only way you know for sure that they're a spammer, is after they've already sent spam using your platform.