Honestly, triple screens is pita to setup, not supported in all titles, have visible bezels, and add significant bulk to the whole setup.
UWDs like 49" Odyssey G9 has been gaining popularity as attractive alternative to triples (and to some degree VR) for a reason.
Can 57" really add much to what 49" can provide already immersion/usability wise?
I would wait for people to compare both, on
diagram the main gain is the width, with curve in place that means only stuff filling your peripheral vision as it is with 49" already.
Headtracking like TrackIR already extends that dimension when you turn the head, personally I do not see this as an "upgrade" path esp. with that bulk and weight that would require separate monitor stand instead of bolting directly to the rig, which defeats the compactness of UWD in comparison to triples in the first place.
May be if it was OLED, I'd consider, but for essentially same display technology with additional requirements for DP 2.1 which no one supports yet, I'll pass.
Most would agree that the single-screen experience can be less fuss/hassle. I know I certainly don't want triples again and the various configuration efforts for different titles, nah nah nah....
Some people may not want the *popular mod via magnifier strips to remove borders solution. To then have those hinder the image quality for general usage and look a bit daft.
We are seeing more and more large-screen options coming to the market. We are not seeing borderless monitors for improved multi-displays becoming a thing. To date, I think the closest thing to a borderless display is only available on Samsung's 8K / 900 series TVs.
PIXELS:
The PPI cannot be overlooked from the upgrade perspective, so not only can people have a large scale of image with this monitor. Offering, more in-your-face immersion with a taller screen area. I think it also offers the highest PPI of any widescreen monitor to date.
The 45" LG Oled = 84 PPI (similar to a 27" 1080p monitor)
The 38" LG 3840x1600 ultrawide monitor = 111 PPI
The 49" Samsung 32:9 monitors has = 109 PPI
The 57" Samsung 32:9 = 140 PPI
The 57" G9 also has the same horizontal desktop as 3x 1440p monitors, so yeah, HUGE and with the extra benefits of being a 21:9 + display if desired or dual 16:9 or dual input display and no borders. It would also be awesome with "Fancy Zones" for multi-window multitasking and combine that with PIP of an external source if desired.
Gaming:
Triple 1440p = 11,059,200
49" 32:9 = 7,372,800
4K 16:9 = 8,294,400
57" 32:9 = 16,588,800
With the 57" it will be possible to still game with the same resolution as the 49" which brings it below the GPU requirements of a 4K screen. Doing so with even better image quality than what 49" owners of previous models have already got used to experiencing.
A downside will be the blooming while reduced on this model (subtitles whites on blacks) are one of the areas the mini led has.
Yet triple 1440p is higher than 4K but without the benefits of its higher PPI and triple 4K is still rather silly if seeking to play many of the modern titles even with the best PC system possible.
More and more titles are coming with support for large screen 21:9 and 32:9 displays.
The scenario for multi-screen setups, is not always well supported or needs additional configuring not just from software but also installation with additional heat, cabling and additional power.
Those would be reasons I would upgrade and I think Samsung know a lot of their customers for this will be people who owned previous models in the past......