What a rapid dropoff for Williams. in 2018-2023, he averaged 60.4 receiving yards and 0.4 TDs per game, which scales to 1027/7 over 17 games. He did that while averaging 15.8 ypr. Those aren't world beating numbers, but those are solid WR2 numbers (in real NFL life, not talking fantasy).
The problem was staying on the field. Is there any reason to believe he can stay healthy and available in 2025? If so, he certainly has chemistry with Herbert, and, as of right now, he is the best X WR on the roster, which could mean he could be the Chargers WR2, with McConkey as WR1 and Johnston as WR3 and playing a lot more Z than X, which better suits his game.
The Chargers have a lot of needs that I expect will take priority over WR in the draft (Edge, IDL, G, C, TE, RB). As a Chargers fan, I'm not super comfortable counting on Mike to be a top 2 WR this year, but that is the current situation, so it is possible.