I get what you're saying. The problem is that it is not really a matter of if plugins are supported or not. Helix will have plugins in the future. There is work being done towards it – mainly design work right now and they try to figure out how to approach this best, writing "demos" etc.

Plugin systems are not easy and they have a clear vision of how this should NOT end up working. In their current state putting in work into a Plugin-System does not make much sense (limited developer time that is better spend elsewhere) regarding their project goal.

As i said you can argue that the project is in its infancy and does not work for you because of that. But the main reason is not the support or lack of plugins. As i said, even if there was a plugin system you could argue that there are no plugins available for the things you want – ending up at exactly the same point you're today. Having a Plugin-System does not magically makes hundred of useful plugins appear out of nowhere.