I hate to say it because he was probably my favorite player on the team at one point but I'm pretty sure Biggio is our version of Gleyber Torres. The injuries last year didn't help but the dead ball is killing him more than anything.
He's a lefty pull hitter who gets shifted, has a high launch angle, Ks quite a bit, and has an elite BB%. Despite mediocre batted ball data that kind of profile played in 2019 but deaden the ball and it will kill someone like that because it's going to take a decent chunk of his homers and turn them into fly ball outs, which renders his already low BA to levels that make him almost unplayable.
Despite hitting 24 jacks in his first 574 ABs in the bigs, his average home run distance was always toward the very bottom of the team around 390 feet. Most guys around the league with average home run distance of 390 feet aren't hitting anywhere close to 20+ homers a season but he was. Deaden the ball and it's not even a huge difference to the eye but if you take 6-10 homers off the board over the course of 160 games and turn them into outs it's going to affect his stat line greatly. It turns him from a .240 hitter with pop to a .225 hitter with subpar power. Pitchers aren't going to respect him as much either so his elite BB% is becoming more pedestrian as well. Regress the lucky BABIP he was getting and his BA continues to crater even further.
He looked like a potential star at one point but now I think he's screwed unless he morphs himself into more of a spray hitter who can retain a solid walk rate. But it looks like we've already got that guy in Espinal who is also a superior defender and there is no guarantee that Biggio can change his game like that anyway. Maybe a ban on the shift will help him but even if that happens the 2019-2020 version of Biggio isn't coming back. Guy looks like a mediocre bench player AT BEST moving forward IMO.