Yes, it seems like we need to follow along here. The question is perhaps if we also should go with --ciphersuites instead of explicitly spelling out 1.3 in the name. Who knows, maybe a future TLS 1.4 can also use it?
No. We already have --ciphers switch. The new --ciphersuites will cause confusion for the users.
Spelling TLS 1.3 is kind of necessary and makes sense when TLS 1.4/2.0/whatever comes out. It simply means the cipher suites are for TLS 1.3 and above.