Did you use a modern TFT/LCD screen by any chance, too?
If so, then it's no surprise. That will double ruin the experience.
To make old games look "best" it's recommended to find out what kind of monitor setup the developers (or the audience) of the time used.
In case of consoles, this also includes the video connection.
For example, the 8-Bit/16-Bit generation was intended to be viewed via RF or CVBS/Composite on the TVs/video monitors of the time.
Playing them on never screens, -even if they are CRTs-, is not "good" .
Modern CRT TVs have poor tuners that can't properly display 240/288p signals.
Or their tuners can't handle the weak RF signals properly, as often seen if someone tries to attach an Atari 2600 to a modern CRT TV.
I guess that's because the modern TV's tuner wasn't seriously meant to receive signals over terrestrial antennas, but rather was designed to receive analogue Cable TV.
Also, these modern CRT TVs may use different CRT mask types that don't play nicely with the source material.
So better restore a 1970s to 1989 TV.
Or one of these little portable/luggable TVs.
Earlier TVs may have issues, too, because their signal stability is likely too poor.
Anyway, the same is true for VGA monitors.
For "best" (most faithful) experience, get yourself a slightly blurry 14" VGA monitor from the late 80s/early 90s and cautiously fix it, if necessary.
If it has knobs and no on-screen display, the better. 😀
"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel
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