Isaiah Thomas is not an NBA player
Barring substantial improvements as the season goes on, Isaiah Thomas is finished as a player capable of playing basketball at the NBA-level. Due to his short stature he always had a razor-thin margin for error on the offensive end. In his heyday, he used his incredible straight-line speed and herky-jerky hesitations to create every possible inch of space from defenders.
Unfortunately, due to his hip injuries and age (turns 31 in February), he can no longer create the separation needed to finish at the basket. Getting to the rim and finishing was always his special skill, so an Isaiah Thomas that can no longer do this is greatly diminished as an offensive player. He has gone from shooting 39 percent of his shots at the basket in 2016-17 (his last season in Boston) to just 16 percent. This has also caused his free throw rates to plummet. IT is a jump shooter now.
He is still a solid offensive player even with these changes, but the issue is on the defensive side. It is not a stretch to say he has been the worst defensive player in the league this season. The Wizards are basically playing 4-on-5 out there. They have had a 100.0 Defensive Rating in the three games Thomas has missed, and a 121.2 (not a typo) Defensive Rating in the 17 games that he has played in. If you are getting special IT performances like in 2017, then you can live with the issues on defense.
With it being over two-full seasons since he was last able to summon this magic, it is safe to say that this Isaiah Thomas is not coming back. Maybe he can still carve out a role in the league as a bench gunner-type, but I do not see Isaiah Thomas lasting in the NBA much longer at this rate.