I understand where you're coming from, but I think it's essential to take a more comprehensive view when judging the progress or development speed of an open-source project.
Firstly, if we are specifically talking about PHP 8.* support, you might be onto something. But it's crucial to understand that the past few years have been challenging for many due to the pandemic and various crises. People everywhere, including developers, faced personal and professional setbacks.
Moreover, the Question2Answer community, although passionate, has only a few active contributors. It's important to remember that these contributors often juggle between maintaining the code and their full-time jobs or other commitments. Their dedication to keeping Q2A afloat, despite personal challenges, should be appreciated.
Drawing from my experience in Development and Designing since 2001, I recall times when software updates came around maybe once a year. Those were significant, packed with essential features. The landscape has since shifted, with many software platforms pushing frequent, albeit minor, updates - sometimes just to roll the version number. It's a trend more prevalent since the smartphone era, but it doesn't necessarily equate to better quality or meaningful enhancements.
To be honest, I sometimes find frequent, inconsequential updates more disruptive than beneficial. Q2A, in my opinion, still stands its ground. It delivers effectively on its promise without constant version rollouts.
Lastly, as a personal preference, I have a soft spot for Q2A. It's built on PHP, a language I'm more familiar with, as opposed to Discourse's Ruby on Rails. Plus, Q2A does offer an API, giving us room to tailor it according to our needs.
In summary, it might be worth looking at the value and stability a platform provides rather than the frequency of its updates.