My take on 17" and 19" 1280 x 1024 screens is that they are good package of availability, price, panel choices, speed and compatibility with old games.
Like mentioned, you can buy a modern screen today in the shop. I have one nice Asus 19" that I sometimes use in my videos to showcase. 5:4 is not 4:3, but it's arguably "close enough" for most. Certainly nothing like 4:3 compared to 16:9.
1280 x 1024 is also a good in-between step between 1024 x 768 and the much more demanding 1600 x 1200.
In games that don't account for the 5:4 ratio, the image will be slightly stretched vertically, making things look a bit taller and thinner, but it's quite subtle, even in DOS games IMO.