Attach skirting boards later due to screed and joint formation?

Yes, you can count on that.

If a risk of mold can be excluded, it is probably purely a cost issue, since we do not install ourselves and receive a (presumably too) small refund for the omission of the installation of the moldings. That means
Cost of later installation - small refund now vs cost of dismantling / reinstalling wooden moldings with gap later
If a gap will be visible on all moldings, it would probably be cheaper to forgo the installation now.

you "overthink" a (small) thing that has already been expertly answered. Just do it :cool:

Can I conclude from this that joints will not necessarily occur, and that I can therefore take the risk of installing the baseboards? The edge cupping is probably different everywhere, so it could happen, for example, that a joint is visible in only one place?

This question, in my view, is based on excessive anxiety. We are in the construction industry here. There are always unexpected situations, thus deviations from the ideal condition imagined, which a client must also accept. Have the baseboards installed and – if joints do indeed form between the flooring and the bottom edge of the baseboard – seal them thinly with an elastic sealant for optical reasons only. Cut this sealant, once it has hardened, through with a sharp, thin utility knife blade parallel to the surface of the flooring. This way, on the one hand, the optical impression of a joint-free installation is given, but on the other hand, the flooring can still respond unhindered to changes in air humidity and temperature with dimensional changes. Regards: KlaRa

Unfortunately, I discovered this thread too late.. For the reasons mentioned by the OP, we decided against relocating the baseboards, and now this said year has passed. However, I am currently wondering how complicated it will be to install the baseboards afterwards, since all the furniture is now in place. Moving a sofa or small cabinet is no problem, but for example, our Pax corner wardrobe, which is additionally fixed to the wall, I can’t just move it easily.

Am I just imagining this too complicated, or does the installer have a trick to still get the baseboards everywhere?

Our floor layer is on vacation, then we are, so I currently can’t reach him either, otherwise I would ask him :D

but for example our Pax corner wardrobe, which was additionally fixed to the wall, I can't just move it around easily.

So 1. you actually think about something like this (furnishing problem) beforehand 2. you leave out the area because it is not necessary.