Dotless domains on gTLDs are prohibited. Technically can work (albeit with risks not easily solvable as explained in ICANN link) but is not allowed.
I would think yes, despite the nomenclature, and that there is technically supposed to be a dot after the tdl.
It's to clearly identify a domain as a FQDN and not as a subdomain of your search domain.
See https://news.ycombinator.com/item?id=24442033 for why it’s allowed on ccTLDs