Lattice cryptography was a contender alongside curves as a successor to RSA. It's not new. The specific lattice constructions we looked at during NIST PQC were new iterations on it, but so was Curve25519 when it was introduced. It's extremely not a rush job.

The elephant in the room in these conversations is Daniel Bernstein and the shade he has been casting on MLKEM for the last few years. The things I think you should remember about that particular elephant are (1) that he's cited SIDH as a reason to be suspicious of MLKEM, which indicates that he thinks you're an idiot, and (2) that he himself participated in the NIST PQC KEM contest with a lattice construction.