I had an app rejected, because it had the word "Finder" in its title ("Virtual Meeting Finder"). I had to change the name of the app, and it wasn't too big a deal, because the original name was fairly unimaginative (as it was supposed to be).
But it does sound like the whole app name is in conflict with a registered Apple trademark. It's unlikely to ever be approved.
You could possibly try to register the "INKWELL" trademark for an RSS reader, since that seems quite differentiated from Instagram's claim, but IANAL, so who knows how successful that process would be.
[1]: https://tmsearch.uspto.gov/search/search-results/86733442
[2]: https://tmsearch.uspto.gov/search/search-results/78126699
I think holding that kind of power over devices people own is problematic, but I seem to be in the minority here.
Much more extreme example, I read a court case where the cops were really annoyed the perp told them they should've been enforcing $muchWorseCrime elsewhere. Judge wasn't a fan either.
You lose a trademark if it becomes generic, regardless of how hard you tried to keep it from being so. Obviously if you let a bunch of actual infringements slide you're on the way to becoming generic, but all that matters is whether the trademark IS generic.
But, when lawyers write letters to people saying "you can't say escalator or Zamboni" you can just ignore them. Using a trademark in writing in a way that a trademark owner does not like is not infringement.
And this is my biggest gripe with products from well-known companies that use already generic terms like "Apple", "Word", "X", or "Inkwell". I understand claiming exclusivity of words like "Microsoft Word", but not for the word "Word" itself.
https://www.dreyfus.fr/en/2025/03/18/proof-of-use-in-the-uni...
I remember when the Apple logo stickers Apple packed in had a little (R), which was later dropped, since it's ugly and not legally required. But no doubt some lawyer advised putting it there to begin with.
I wonder if there was ever an epic Monster sugarwater vs Monster Cable showndown.
Mediocre ones seem to cause the most problems.
Maybe they always scroll that trademarks page, they're just really thorough.