Actually, there are huge skepticism about small exchanges running IEOs because the hype hasn't come yet. Should there be the hype again, they're all gonna run very successful projects but you're right tho, proper research should be done before joining IEOs.
It's not because Hype, the skepticism about small exchanges running IEO is that the exchanges hasn't yet become reliable and proven to be trusted, the devs that want their project listed on small exchanges' IEO could bribe them anyway.
That's why there's no guarantee that an IEO will not turn scam if the hoster is small exchanges that is not popular even worse the exchanges is created only for IEO and just recently.