I've managed to resolve this issue on my PC (i5 12400f, 3070ti FTW3, 3200mhz 32gb cl16, game on nvme, 1440p resolution, newest nvidia driver, latest win11 update).

It may sound dumb but after all the searching and messing with drivers, windows settings, switching to lower resolutions, all I did was turning the textures to the lowest available in-game setting. Game looks like trash now but there are practically no frametime spikes (checked in rtss aswell, before and after). Difference is night and day. Game works almost flawless now, spikes still appear but except a spike every 10 seconds or so, now they appear a few times per game and in killcam, after death or in menus.

I also don't use the texture streaming and all the other graphics settings are turned of or set to the lowest. DLSS is set to quality preset and fov is 110.

If any of you had tried this already than I feel sorry for you as it is actually quite gamebreaking if you expect a reasonable and stable framerate (which this game is absolutely capable of delivering)