As much as I understand the iconic status of Luna, Windows XP"s default green and blue theme, the Classic theme has always been a special one to me. There is just something extra cool about the utilitarian and industrial looks of the gray user interface with sharp corners, contrasty elements, and buttons that feel like you can press straight through the screen (and that teal desktop background).
For better or for worse, we are no longer in the 90s, so we have Windows 11 with its sleek UI, rounded corners, and transparent elements. Even though I am not a fan of modding an operating system"s looks, I just have to admire the effort it took for someone to turn Microsoft"s latest and greatest (arguably, of course) operating system into something that looks like a piece of 30-year-old code capable of running stuff like Discord, Telegram, Steam, and more. Here is Windows 11, which looks like Windows 95.
Since Windows 11 is more limited in terms of personalization compared to its predecessors from the early 2000s, getting it to look like Windows 95 or Windows 98 requires some extra effort and the help of third-party apps. According to the project author, who posted the result on Reddit (via XDA), you can apply an old-school coat of paint to Windows 11 with the help of apps like Windows Blinds from Stardock, Retrobar, Winaero Tweaker, and some skins for third-party apps (Steam, Discord, Telegram, etc.).
While nostalgia often feels good and invokes sweet memories, I would probably not run such whacky experiments on my primary machine for stability and integrity"s sake. Still, if you have a virtual machine or a spare device to experiment with and some time to kill, it is definitely a cool thing to toy around with it.