Why do publishers announce their games on GOG, yet have no game page? Is publishing on GOG that complicated?

According to the latest trailer for "Oddsparks: An Automation Adventure", HandyGames and Massive Miniteam will release the game on GOG, but it's nowhere to be found on the storefront... I feel like this is not the first time such thing is happening. In the big scale of things, wouldn't it be smarter (business-wise) to help those publishers when it comes to creating a page for their products?!

Could be any reason from technical complexities to simple laziness on the developer's/publisher's side (they'd be required to fill out some sort of form, providing not only general information but media (pictures, trailers) to be put on the store page, I assume).

To be honest I'd rather the publishers not put up their games in the catalogue until they're ready to start selling it. So if that's why, then I applaud it. A few games here have been stuck on a permanent "coming soon" for a very long time in this store, which is disingenuous when it seems to be clear they're not actually going to release on this platform until years into the future.