Certainly not via route servers or typical bilateral peering configurations - but transit-over-exchange is a thing, if you can find an exchange participant willing to offer it to you.
Yes, but the question is, is transit over exchange better/cheaper than buying a crossconnect? Worst case you've just introduced another dependency that costs money and adds complexity. If you're on an IXP, you're already somehow in a data centre anyway… that will have been the hard part in most cases…
> question is, is transit over exchange better/cheaper
Better? No, almost never. Cheaper? Sometimes, especially in DCs that charge ridiculous MRCs for cross-connects. For a small/personal ASN, it can be the right choice.
