I am afraid I will have to strongly disagree with you there, the old planetary tech certainly didn't generate better looking planets!
When it does well, it does very well. When it fails, it really fails hard. It's a lot more extreme, both ways, than Horizon ever was.
Also, so far, all planets I've seen in Odyssey are, how should I say, generic ? Essentially, they follow the same pattern, we have a few patterns, but overall, all the planets belonging to one group look kinda the same.
Like the "chocolate" ice planet, the "dessicated clay" planet, and so on.
This is further magnified by the lack of RNG on assets like rocks, and how few of them there are in the database. More often than not, I find the same looking rock all over the place, and it's quite jarring.
Despite Braben being known for his work on procedural generation, the game use very little of it, and seemingly, even less now with Odyssey. While the planets are procedural, they all follow some pattern. And very little else is procedural.
There is also the feel Horizon had more details when far away from the planet. Enough to hide the repetition, like the infamous big crater. Odyssey doesn't, and we get to see all that repetition in all its glory.
There are also big issues with LOD and poor quality terrain/loading. A few examples :
"south" pole of the planet.
The weird glitch was moving around as I got closer, until it disappeared and the planet became "normal".
Or :
Very blurry, as if the planet was at a very low resolution. It's less visible on a screenshot, but it's quite jarring ingame.
Or this :
As you may notice on the upper left corner (it was also on the right, but it's harder to notice on a screenshot), the planet edge is VERY blurry. In fact, the entire planet started as blurry, but as I came closer the "blurriness" was pushed to the edge of the planet, and eventually replaced by more normal terrain.
This is only random observations I cared to screenshot in a few weeks with little time spend playing. The first screenshot was a planet I crossed when looking for G3 gear, the second was the one my FC was parked around, and the 3rd is a conflict zone from a recent CG (the one about the Emperor abductors).
Either I'm the most unlucky person in the game, or those are quite common.
And obviously, we have the few "pre made" planets, who still look like trash, like the one in my signature. I mean, that one is now puke green and not grey, since the "planet" patch a few months ago.