El-Sayed ran on Medicare for All. It's totally fine - in fact, appropriate - for him to be advocating for it in the Senate.
The key word in his tweet, though, is "pass." If the votes to pass M4A aren't there, Dems should obviously not offer it up for a vote.
What is the purpose of this commentary?
We just had an election. Nine seats flipped. Only one of the seat-flippers embraced this idea in the campaign. Why the determination to make people mad at the people who just won?