> So apple is just selling generic white labelled slop

There are only ~5 flat-panel manufacturers worldwide: AU Optronics, Innolux, LG Display, Samsung Display, Sharp Display, and recently BOE Display. Apple has to use one of these, even for its bespoke, notched, curved iPhone/iPad displays.

This new 5K 2304-zone panel was developed by LG Display, and is not 'generic white-labelled slop' by any means. It is an extremely good panel in its own right, probably the bleeding edge of LCD technology today achieving top-notch responsiveness, contrast, and colour depth and accuracy.

That MSI monitor will probably retail for ~£800 as will the Asus and LG equivalents, which is not a trivial amount for a monitor. Apple just marked it up 3×, as they are prone to do for anything.

The Apple monitor will likely have better speakers, and I'm not even sure the others will have microphones at all. Apple also does a better job with color accuracy/consistency, at least historically. There's still a sizeable markup, but it's not entirely for nothing.

Back in the day (~15 years ago), when 4K monitors were unheard of and even Apple's high-end displays were still 1440p, you could get a bottom-dollar monitor using one of their panels (e.g. Yamakasi Catleap Q270) for about a third of the price. However, it came with no amenities, a single connector (dual-link DVI only), a questionably legal power cable, and no built-in scaling. The vendors, presumably to prevent refunds, even asked for your graphics card model before selling it to you, because it wouldn't work with low-end cards. Oh, and there were very few in the U.S., so you were typically getting them shipped straight from abroad, customs duties and all.

We've definitely come a long way.