If it makes you feel any better/worse, a publisher is also likely to leave the marketing up to you, beyond making it available to purchasers and one or two half-hearted "marketing" actions that basically consist of sending you to a convention or two.

Books don't earn out their advance unless your first name is a ball of initials.

To be honest I don't know anything about marketing or publishing books, but I couldn't imagine promoting anything on tiktok either. Thanks for the response. Best of luck with your book.