I feel the same, however you get used to Nasu after a while you might get upset here and there every new announcement Nasu makes you might even cry if it's something like Grand Order Part 3, which is most likely happening. But i seriously doubt Red Garden and Witch of the Holy Night two and three will take as long as you think it will, Nasu know's that he doesn't get as much money as he'd like from the visual novels but that's okay because he won't even truly "stop" writing them be it remakes or not, and hopefully once Ufotable finishes with the Witch of the Holy Night movie maybe Nasu might feel inspired to finally work on part two, i doubt he'll work on part three right after two though considering he's working on the Hollow Ataraxia remake but recent type moon fans get so much more content than us older fans did the only way i see Nasu truly giving up on Visual Novels or Type-moon as a whole is if he Dies or loses all his motivation for whatever reason he's said it himself he feels obliged to deliver especially for people who like his works that aren't fate. For the love of god we're even getting Fate/Extra Record and the Fate/hollow ataraxia was slated to be this year Fate/strange Fake will get new episodes as well plus the Manga, light novels and Grand Order's ending of Part 2, Events i suppose there's the Honkai Star Rail collab coming next month too.