So uh...Digimon Seekers being a web novel will be interesting.
It's an interesting format for sure. I'm guessing they're trying to find a way to keep "constant content" going in light of the loss of the anime timeslot and all that (the card game's doing well, but there's only so much it can do by itself).
Speaking of which! Let's talk about the elephant in the room, which is Digimon losing its timeslot and Ghost Game not getting a follow-up anime! In previous occasions, every time Digimon lost a timeslot and the anime went on hiatus again, that meant the franchise was in danger of dying (again), but...as of earlier this year, Digimon is now Toei's third best-selling IP internationally. So it is highly doubtful that the anime is going back on hiatus simply because things aren't doing well.
So, what's actually going on?
We're used to the idea of "Digimon should run back to back if it does well," and that's true of series that are explosively popular (which Digimon is not right now, even if it's not on the verge of dying either), but in actuality, the Fuji TV 9 AM slot is a high-demand one to the point most franchises don't get to run for three years on it consecutively. That kind of thing is rare enough that Japanese fans familiar with the timeslot have commented that Digimon has probably accomplished a lot getting to keep it for the last three years. There are only two IPs that have ever gotten to run for four consecutive years or longer on that slot: one is Dragon Ball (I think "not being as profitable as Dragon Ball" is hardly something to freak out about), and the other is Digimon itself.
That financial report I just linked says that Digimon is Toei's best internationally selling IP including overseas sales. While we've had a lot of reports recently about Digimon's financial success, they all specifically note that it means internationally and not just Japan -- and, granted, that's still important especially because Toei and Bandai have been trying to aim for more of an international market in recent years, but that's what's telling us that the video games and card games are what's carrying Digimon now, not necessarily the anime, which currently has very little influence outside Japan besides the Crunchyroll simulcast (and probably some East Asian language dubs), and I imagine that doesn't contribute very much. And the Adventure: English dub doesn't seem to be coming out anytime soon...
Like I've said, the card game is doing great, and sets have been coming out in Chinese and Korean as of late.
So while I'm no financial analyst, I'm guessing they've decided to put a hold on the kids' anime right now because it's not a very good outlet for their current best option, which is to focus more on building an international market and solid base. That doesn't mean kids' anime will never come back, and it also doesn't mean the franchise isn't already in a much better situation than it was when Frontier, Savers, Xros Wars, and Appmon ended, because the recent success of the video games and card games gives them a lot more of a foothold to do more business ventures, and maybe they can funnel that into actually getting partnerships to dub future kids' anime if they want to do that again. Moreover, it's true that in the past, the franchise would hit life support every time the anime stopped, but that's because the franchise was dependent on having a running anime for attention, which is not the case now because the card game has been doing fine independently of the anime. So I think it's pretty easy to understand that having an ongoing kids' show won't be the best option for them at the current moment, and meanwhile Digimon Seekers is coming out in multiple languages at once, so you can see what the strategy is here.
Of course, I think much of Digimon's best content is in the kids' shows, so I hope it comes back (and I'm certainly not a huge fan of the idea of the only anime we get being from that pipeline that's focusing on nostalgia stuff with Adventure branding), but that's how I see it for now.