Neemias Queta was one of the primary factors why the Boston Celtics played as well as they did during the regular season. It really seemed as though he had become more disciplined and, by extension, a two-way force. However, he's been the exact opposite in the Celtics' series against the Philadelphia 76ers, exposing that he is not their center of the future after all.
To put it bluntly, if Boston is serious about winning more titles, this series has exposed that Queta can't be their starting center going forward. This has been his biggest test as a Celtic, and he's failed pretty spectacularly.
Queta has not been good throughout this series. He's had exactly two solid games for Boston - Game 1 and Game 5 - but he has failed to make a noticeable overall impact in this series. The aforementioned discipline that made him a force to be reckoned with hasn't been there against the Sixers.
It hasn't been one thing, but many. It starts with his foul trouble, and that was a problem even before Joel Embiid returned. He's accumulated too many fouls too quickly consistently throughout this series. The discipline that kept him consistently on the floor has seemingly disappeared.
But there are other problems besides that. For all the good Queta previously brought on the floor, a stretch big, he certainly is not. Philadelphia is taking clear advantage of that, as their strategy has been to clog the paint for Jayson Tatum and Jaylen Brown. They don't fear Boston's other floor spacers, like Sam Hauser (he's proving them right), and Queta's presence only plays into their hands.
He has also not had much luck against Embiid. His best defense against Embiid has been hoping for the best when Embiid takes a jumpshot. Queta was an excellent defender all season long, but Al Horford, he is not. And to be fair, his defense didn't fare too great even before Embiid returned.
For the record, if Boston had won this series in Game 5, they could have brushed this issue off, since it clearly wouldn't have hurt them. But it is, and now they're on the verge of blowing a 3-1 lead to the No. 7 seed and a team they've beaten the previous three times they went up against him.
Nikola Vucevic & Luka Garza haven't been much better, but match up better vs. Philly
In Queta's defense, neither Vucevic nor Garza have asserted themselves well enough to make Queta look worse. They are not the rim protectors Queta had proven himself to be up until this series took that out of the equation. However, they at least are more multi-faceted than Queta is on offense, stemming from the fact that they are floor-spacers.
They may not add much more defensively than Queta, so at this point, Boston's best defense might be to make Philly's defense have to work to slow them down. Queta not being much of a factor has made it life easy on the defensive side for them. Vucevic and Garza at least makes them have to work.
The overarching point here isn't even about Queta. It's more to point out that Boston's frontcourt problem that many harped on, only for them to then impress, has now been exposed as a real problem in these problems.
It's not that Queta isn't a bad player, period. It's that these playoffs have exposed that if the Celtics want to be a feared contender, their starting center has to be much better than him.