Toilet too high - lower it or leave it as is?

I would also have it measured first before giving any advice here.
Say, the reason is the screed?! What does the screed installer say about it?

Ok. As I said, the contractor said it would be better for the drain. That also made me skeptical because in my opinion it's rather the other way around. So raising it is better for the drain but lowering it is not.

Because of the height. I will measure it exactly later. No, my wife is not particularly short. Don't let me lie but I think she is 1.73m.
I am 1.81m and for me that is also a bit uncomfortable.

Yes, the screed layer is not really helping us with that now. As I said, we already live here. The screed layer can't just dump another load on top.

Why is it then only the toilet where the height is wrong? If I imagine that there is not enough screed, wouldn't everything have to be too high?

Well, elsewhere it doesn’t stand out. Whether the shower fixture is 3cm higher or not doesn’t matter. And the large vanity cabinet on which the two washbasins sit was installed only after the tiles were done. So it was measured from the finished floor.

@Mycraft Why do you think it doesn't work as described by @cschiko?

Because you're dealing with a toilet that's too high. However, these "botch kits" are meant to make toilets even higher.

That a higher toilet is better for a drain goes without saying. Because this way the water (and other components) experiences greater acceleration and thus flows away better overall.

I know the situation of an unusually high toilet from our panel van. Here we solve this with a footstool, which is optionally available. Whether I wanted to have this as a permanent solution in the house is questionable – in any case, the sessions become more comfortable for the shorter one of us.