ESW shares resources across all applications on their portfolio. So, you could say that there are 0 DNN employees. You could also say there are dozens of DNN developers.
ESW is responsible for development / support of Evoq. I don't know how that is going for them or their customers.
We - the community - are in charge of the DNN platform code.

Building on the core version is done in Github. You can make pull requests to change or add stuff. If you want to know more, have a chat with Peter Donker.

I am a long time member of the DNN community and core team (starting at the times of DNN 3.0) and- with all respect to my friend Shaun - am having a different memory and view on the evolvement of DNN and the role of the founders and DNN Corp.,which renamed the product (from DotNetNuke to the weak DNN bland), removed all modules from DNN distribution, squeezed out all development efforts to DNN platform from the community and acquired the best talents of the community - for a short time before providing them with a pink slip and detailing them from further contributions th the product and community.
When ESW acquired DNN Corp. (being in a very fragile state at that time), they handed over control for DNN platform to the community, i.e. dozens of volunteers forming different teams and trying hard to get the product back on track and ensure it to be a true Open Source product - in the ownership of the .NET Foundation (https://dotnetfoundation.org/). This was a tough set of tasks, to move over all processes and infrastructure to the community and get them back running (which is not completely finished yet).
Within these new community efforts, the Technology Advisory Group (TAG) is taking care of product development, including fixes, release process and strategy for future versions. We are well aware of the need for a change to .Net Core as new technical base. However, after extended investigation, we decided for our roadmap to fix a number of shortcomings of DNN platform first to be able to provide the best upgrade path for all existing users. This is work in progress and we welcome anyone, who is willing to contribute.