Will Microsoft Flight Simulator support multiple monitors?

I'm not sure I'd use the phrase "worse than the old version" myself.  The graphics are stunning across the globe.  I'm not a proficient enough FS pilot to determine if the flight models are actually better, but I understand they used way-more complex modeling to make flying more realistic.  That being said, you are right, the old version had good multi-monitor support.  I read somewhere they are aiming to add that later in 2021.

Oh no... I purchased the 2020 version assuming it allows multiple screens for different instruments as this feature was part of the old flight simulator. Seems as it doesn't. So it is worse than the old version?!

RE: Being able to run the replay of takeoffs and landing.

YES, YES, YES, this is a sorely missing feature of FS2020 and is badly needed IMO!

This was one of the greatest features of FSX, not only the replay capabilities, but also of the graphing capabilities of the flight, and the final approach (speeds, descent rate, altitudes, etc.) which is essential for evaluating how well a precision instrument final and landing is flown.

COME ON FS2020 DEVELOPERS, ... LETS GET SOME OF THESE BEST KNOWN AND LOVED FEATURES OF FSX BACK INTO FS2020!!

You can span the display using Nvidia's Surround, which is part of the Nvidia control panel. 

There is something similar to this if you are using an AMD video card.

At present, FS2020 DOES NOT allow you to open new additional windows for separate instruments, views, etc., like it did in FSX.

Hopefully Microsoft will address this in the future, and make this benefit available, ... although I doubt it, because the software is designed to mainly run under an XBOX single window environment (using either a PC as in XBOX Beta for PC or on an XBOX console.)

I'm currently running FS2020 using three screens with a resolution of 5760 x 1200, and FS2020 runs fine across these three monitors which are in Nvidia's Surround (so it looks like one big, very wide screen monitor.) And this works great, EXCEPT it would be nice to be able to open up another window for just the instruments, like I could do under FSX. 

One of the trade-offs, of going with the much, much, much more advanced FS2020 software.

Yeah its absolutely right i am also working with the same setup,  **"EXCEPT it would be nice to be able to open up another window for just the instruments, like I could do under FSX. "**and just like in fsx the replay also so we can check the landing and take off perfection.