[Tomte]

That's because the usual Computer Modern font files today are too thin.

Knuth designed in a "blacken" factor and gave instructions how to tune it to your specific printer.

Because the correct amount is dependent on your printer and its printing technology. Ink tends to blur a bit, for example.

There are font files around that try to make CM a bit more correct on typical printers today, but most people don't know about it and are using some bad default CM.

[bombcar]

This is similar to how the “pixel art” versions of old console games never existed because the TV CRTs didn’t have definite hard lines between pixels. Computer Modern was designed to be bitmapped when printed and so took into account that it would all be dots not infinitely thin lines.

Amusingly enough, this is basically "The Renaissance" done in a short time; just as they perceived the "Greek" style as bare marble statues and buildings which never actually existed.

[mrob]

LCD-based portable consoles existed. The Sega Nomad ran the same games as the Sega Genesis, which are often said to "require" CRT blur.

[moshmosh]

If the Nomad's display was anything like the SMS-based Sega Gamegear, then it may not have had CRT blur but it did put its own not-so-crisp spin on the picture:

https://youtu.be/pU4jnSVfZsI?t=188

(left side at the time marker is the original Gamegear screen, right is a mod with a modern screen)

Oh, found one of a Nomad with the original screen:

https://www.youtube.com/watch?v=9j0mXNb6YPk

Similar. A little less washed-out, but still not what we think of when we think of the precision of a modern LCD.

As I recall, LCD PC monitors until some time into, I dunno, maybe '05 or so, were regarded as almost always worse than CRT monitors in practically every way[0], including picture quality. Better than a typical consumer tube TV, maybe, but even some of those produced a crisper picture than a lot of LCDs, especially tiny low-power ones like that (the Sony Wega comes to mind)

[EDIT] [0] Practically every way except size & weight, I mean, obviously, and despite crushing CRTs on that front, were pretty unpopular due to being so much worse otherwise.

[jimhefferon]

I remember two recent uploads to CTAN: https://ctan.org/pkg/mlmodern and https://ctan.org/pkg/newcomputermodern. FYI. Never tried them, myself.