I have the TUF AX3000 v2, which has no Merlin firmware alternative, but it seems I can try the latest Gnuton instead!
I'm a newbie, so let me ask: why does the firmware filename (TUF-AX3000_V2_3004_388.9_2-gnuton2_nand_squashfs) have the extension .pkgtb, and not the extension .w, as is usual...