but all proprietary and as locked down as possible hatdware-wise.

There’s no DRM in the hardware. It isn’t locked down at all. There are 3rd party hotends already. Not even Prusa has open source hardware now.

I am fairly confident they will follow a similar path even though they have made some software source - available.

They have released all firmware source code. So it doesn’t matter what they do in the future. You have control over your hardware for forever.