Using ballpark numbers, he played less than half a season fit, from memory ~30-40% of all available minutes. That's 1/3 of a season, of which he also took 10-15% of the time recovering match fitness. That makes about 20% of ALL the matches he played that are worth any assessment, all of which occurred in the stretch of games between Oct-Nov 2019 - where he played quite well until the Meunier foul. Beyond that he had zero time to develop any sort of chemistry with the group.
Plus he drew the most (or 2nd most? can't remember) fouls and penalties on the team despite being out. Which proves he DOES add things even when mostly poor.
We're not better off working with the young all the time, they'd need to learn too much too fast. Selling Hazard is also not an option because a) nobody will pay enough as he's too old and hasn't featured consistently in ages; b) Perez will never resell as it'd mean he has to admit a mistake.
Right now the moods around him are actually better. Everyone is kind of expecting him to get reinjured so no pressure on his ass to return for good. But he's also saying stupid shit like "this draw tastes like a win" so he's being beta as expected. He will be useful when fit, but I don't expect too much.