Even though I often take a centrist-ish position in many debates in practice, I'm philosophically pretty skeptical of self-assessed centrism, both descriptively and normatively.
Descriptively, consider any 1-dimensional axis of variation, of either belief or ideology. Say American left-right politics, or tech vs humanities, or p(doom) from advanced artificial intelligences. Then, as long as you're not at the literal endpoints of this 1-dimensional line, you'd always see people on the left and right. Furthermore, due to various biases like selection effects on who you interact with and outgroup or fargroup homogeneity, you will in practice often see equal numbers of apparent positions on your left and right. This does not mean your position is actually in the center!
Btw the above might make it sound like it’s impossible or very difficult to tell whether your position is actually in the center. But the reality is that it’s very easy to figure out if your position’s actually centrist, if you know how to look. But you need to actually look, rather than just vibe it. (Exercise to the reader to figure out how).
I think many other people have made the points about being skeptical of centrism normatively. So I won't belabor the best arguments against centrism here. One thing I'd note however is that if you look at historical debates and judge them with modern eyes (for example, Athenian vs Spartan views on democracy, or Catholic vs Lutheran views of God, or whether the Spanish empire should enslave locals vs enslave purchased Africans), it is not the case that the relevant options for what's "correct" between A and B are one of A, mostly A, B, mostly B, halfway between A and B, or a synthesis of A and B. Sometimes the correct answer is far more in A's direction than A ever argued (or perhaps even believed). And sometimes (often!) the question is so ill-posed that the right answer is very much on an entirely different axis than either A or B.