Posting on the forum is completely unlikely to be an actual drain on the comic though. It takes only a few minutes to type something up or to answer a question and even less time to read it, whereas a panel on the comic could take anywhere between an hour or two days to get just right depending on his process.
Posting on the forum is a good sign regardless, it shows us that he remains invested in the project and the small community that's sprung up around it and it'd be easy to call the comic dead otherwise.
If you want more regular updates (or at least, more frequent updates

I do recall some talk of a Patreon thing. Not sure what's happening on that front, but I assume it's getting eternally delayed for the same reason as the comic; Arioch being eternally swamped with work.
I'm not privy to Arioch's private life (the guy deserves his privacy after all) so all I can really do is speculate, but it seems the most likely reason given what we know.
Look at it this way. The comic has had irregular updates for about 15 years now and is still going. Sometimes we get a good year with lots of updates, sometimes we get a bad year with updates far and few between. And its still here. Still going. That's dedication you've got to appreciate.