https://www.kickstarter.com/projects/1639370584/mapmaker-the...
Linux is a copy of UNIX. Who cares
Ulysses is a copy of the Odyssey, Minecraft was a copy of Infiniminer, Stardew Valley copied Harvest Moon, Fortnite copied PUBG, film directors copy and spread each others’ techniques and storylines all the time. George Lucas even admits that Star Wars was heavily based on Kurosawa’s The Hidden Fortress, while Kurosawa’s film was derived from historical plays and John Ford’s westerns.
"Blue Prince" is heavily inspired by earlier works, those works just aren't video games. You could say the same all the way back to ADVENT, the Colossal Cave Adventure of the 1970s being inspired by adventures in an actual cave.
Of course good games do something we haven't seen before or do it better, but they are also invariably products of a wider culture. A big part of why Animal Well doesn't need to explain itself is that a modern video game player knows how this sort of game works and so when they get Slink or B Wand or similar they realise they can explore places they couldn't reach before.