Here is the list of blocks/plants that we get on the planets, next to their name you can see the number of colors that we still havent seen. If you go to the original post of that quote, you can have all the detailed numbers for each resource.
I used rocks in my OP because it was easier to focus on one single block to bring data for it. If i had to do it with all the blocks, i would have needed the whole week to do it.but from looking at it quickly, i can assure you that we did not get to see more than 100 different colors of flowers/plants. In fact, the only thing we saw more than 100 colors of is gleam. though, that is just according to data, keep in mind that some resources have data but cannot be actually found on planets (i.e Sochaltin has night azure gleam. we’ve looked everywhere and it is not there)