That's the wrong way around, I don't think any conventional analysis of voting systems concludes that.

FPTP forces parties to the center, because they have to be pre-formed coalitions before going to the polls. Single issue parties and fringe parties end up with nothing in FPTP.

That's why the usual argument for PR is that it allows smaller (fringe/extreme) parties to exist and have influence, so represents minorities better.

In practice this is what we see. Countries with PR often have very powerful fringe or single issue parties (often the Greens), whereas in countries with FPTP the main parties are all big tents that just represent the centre-left or centre-right.