Except Boras will want a 4-5 year deal and this team wont be competitive for the first two years of it.

Sign Max until he is 40. Except for Warren Spahn, 40 years old is The End. (And, for the record, Spahn won 23 games when he was 42, and led the NL with 22 complete games). A Boras 4 or 5 year deal  is nuts, unless the 4th and 5th seasons are a team option.

Incidentally, if the Nats won't be competitive in 2022 and 2023, then they won't be competitive until Soto is gone. His contract is up after 2024, so the Nats need to sign him or trade him by the end of 2023. Might as well trade him in 2022 to get anything back.