you're right, tiling multiple small windows within the screen just isn't optimal. a split monitor is still much better, especially when gaming.
I recently bought a LG 38" ultrawide (LG38WN95-C), thinking that it'd serve as an improved multi-tasking monitor over my previous 27" and 23" separate monitors. duno what I was thinking.
for gaming, I absolutely love it. I think I did experience one game that clipped the top and bottom of the image, but it was some indie game I don't play normally and I haven't had the issue in any other game, and I've tried a few dozen. It seemed to work fine in Counterstrike, and I don't think anything was clipped, but I could be wrong.
the productivity improvement I expected with this monitor was a bust.
unfortunately, I learned too late after ordering it that the Picture-By-Picture multi-input functionality does not work when combining Display Port and TBolt connections. Apparently, that detail is buried in some youtube review, and nowhere else in the official product details or the Rtings review. I thought I did exhaustive research, and I'm kicking myself for missing this. In hindsight, I should've gotten a 34" UW and a sidecar.
I need Display Port for my PC (as Adaptive sync is capped at 60fps via HDMI, which is stupid on a monitor rated for 144hz), and TBolt for my work laptop. I guess I could try an HDMI adapter for the laptop, haven't done that yet.
TLDR; Despite slightly regretting the expense of the 38" monitor, I absolutely love ultrawide gaming and I couldn't go back to anything smaller than 34" @ 2k. Maybe I could live with 32" @ 4k, but I'd still prefer an OLED 40" @ 4k (LG C2?)