This position comes from Koivisto-Rubichess, TCEC Season 22 League 1, after 33...Qc2-Qc6.
[FEN "6k1/4b1p1/2q2p1p/r2n4/8/5QB1/5PPP/4RBK1 w - - 2 34"]
- Material is equal
- White has the bishop pair in an open position, but all the pawns are on the same flank, so the long-range ability of bishops should be less important
- Both kings look reasonably safe
- It's true that Black just moved into a self-pin, but 32...Qc6 was not forced; if the pin is actually an issue Black could simply not have moved the queen there
Yet Koivisto signaled a +2.4 advantage for White in this position, Rubichess was almost as pessimistic (+1.7), and so is Stockfish (Lichess Stockfish is +1.7 at d=31).
Where is White's advantage coming from?