No, I get those all day long. Both zone transfer requests and attempts to do dynamic DNS updates which my DNS does not support dynamic DNS. My daemon will respond to those with rejected and NotImpl. Neither my DNS daemon nor the OS even responded to these probes and it was not even my doing. No SynAck from me so the kernel knew these were malformed or something I've enabled logging of invalid packets. Maybe they will try again.

For completeness sake TCP is used for a few other things on DNS these days such as falling back to TCP when the client does not support EDNS and the packet is bigger than 512 bytes which is common with DNSSEC. I do not have any large records. TCP is also used when encryption is implemented (DNS Over TLS) but that is usually on port 853 though it can be supported on 53 encryption can be opportunistic.