Yes that’s definitely rude. To be fair, as Mark mentioned, they probably didn’t realise that the rejection message would be shared with the prospective tenant. Plus if the landlord was receiving a high number of enquiries, they probably didn’t put much thought into their messages anyway. Hope you find something!
However, it could be that English or grammar in general isn’t their specialised subject and it could mean that they substituted the word ‘like’ to mean they weren’t interested, maybe?
By ‘not interested’, meaning they had already agreed a let, and just putting anything to get the boxes filled.
I don’t see how it could be personal as there’s nothing you have said to illicit that response.
You are clearly quite literate and articulate and they simply don’t have the same skill set.