Bobby Hart had a very good season in 2019.

[WeezyBengal]

How many sacks an offensive lineman gives up doesn't tell the entire story. That's like judging how good of a fielder a shortstop is based on the number of errors he has.

Sacks given up doesn't take into account other "bad" things an offensive lineman does and other "good" things an offensive lineman does. I couldn't tell you if Bobby Hart is good or not but it's going to take a lot more than sacks given up to determine that.