I don't think concerns regarding Maluach are entirely unfounded. Over his last 5 games, he's averaging 3.8 ppg and shooting 44% from the field and 47% from 2pt range. For a guy who takes nearly all of his shots at the rim, that's a fairly rough percentage, and the scoring output is less than half of his season average. His TS% is 47.7% in that stretch, which is quite low. He's had a negative BPM in 3 of the 5 games, and a BPM below 4 in the other two. And offensively, his OBPM has only topped 0.6 once in the 5 games, with 3 of them well below zero. It's a pretty fair assessment to say that he's struggling a bit at the moment.
That said, it's also simply a reality of his game at the moment. Despite being a quite good FT shooter, it appears that he's not given the freedom to create his own shots. We're talking about a guy who rarely dribbles. Guys like that are going to be limited to dumpoffs, putbacks and lobs. And right now it seems that teams are protecting against the lobs.
It's also just a five game stretch, so hopefully it's just a bump in the road. But it's a legit concern for the time being. We could really use him returning the 7+ BPM guy he has been for much of the season.