The ST actually has much more CGI than any of the PT film; the issue is that CGI of that scope back in the early 2000s was widely unheard of. As such there was a lot of growing pains and ILM was still trying to figure out how to properly work with the technology and make it look convincing. So all these practical effects, sets, and real locations get overlooked because the CGI at the time just wasn’t 100% ready yet. Not saying that magically makes a lot of the CGI good, just that there is a reason.
But that’s also a problem with the decision making. If the technology isn’t ready, you don’t use it. Or you think it is ready and it’s not and you’re just fooling yourself.
There is also a lot of special effects in the theatrical OT that looks bad (Jedi is particulary bad, but Empire is also not as good as Star Wars). The only difference is that in the OT they only used such effects when they had no alternative (which is why the OT reuses small sets all the time or it has relatively modest action scenes), while in the PT Lucas basically went free and did whatever he wanted without any consideration to how the movie would look years later.
Unless I’m mistaken, the space shots of Naboo in Phantom Menace were rendered, and the planet looks like ass, while Hoth or Dagobah still look decent almost 40 years later.