Been a while since I've played on a regular monitor, but I could have sworn the vertical FoV was higher before I made my switch over to ultrawide, even if I did of course gain some horizontal FoV...? Which... seems fair. If you had the same horizontal FoV as an ultrawide, you'd have hugely more vertical FoV, and if an ultrawide had the same vertical FoV, that'd mean they'd have hugely more horizontal FoV.
Would simply test rn, but swapping down to 16:9 aspect ratios just crashes the game for me.