It's interesting to me that while some of these microcontroller chips (fast enough to do vga) have been around 15 years or so, it's only in the last 5 years or so that people have figured out how to bitbang pretty decent vga output from them.
And now that we have 100Mhz+ microcontrollers people are making really simple devices that take advantage of it. I was pretty impressed with this $11 ESP32 gadget that replicates what an old VT100 would do, but with vga output and a ps/2 keyboard. It also does retro games: https://www.tindie.com/products/ttgo/lilygor-ttgo-vga32_v14-...
Beyond that I guess the main limitation these days would be to find a VGA monitor
The Basic Engine is based on the 8266 (4 MB of flash) and has a separate hardware video controller chip, plus an I/O expander so at least three chips. It has way more "custom hardware" than the TFA's board.
To take the game from the article as an example. http://www.voja.rs/PROJECTS/GAME_HTM/screen1.jpg This one screen depicts seven floors and a bunch of objects. You can see a lot of things well before you need to interact with them. A lot of 3d views limit the scope of what you can see so that the game becomes 'Here's a thing, deal with it! Here's three more things, deal with them! Here's another...'
There's also a bit of a disconnect between the visuals and reality of a lot of modern games. When everything looks near photo realistic, you expect to be able to walk through that gap in those rocks over there, but actually your hitbox is a little large and you won't fit. You don't get those ambiguities so much in 2D. Partially because of the abstract nature makes traversable/non-traversable quite distinct, but also because the view you are seeing will have been seen by the level creator.
Arbitrary points of view allow you to look at a game in a way the creator didn't and can potentially expose missed details.
I think some of the changes are just styles of design that have drifted over the years, some of those may have been driven by technical issues but now exist on their own. For instance early 3D games had much lower frame-rates which mandated a type of gameplay. Those limitations are now gone, but I think it left a lasting effect on the style of game that people made.
I guess that is why Lego and Minecraft are fantastic.