Generally no, they are interchangeable. The only difference being that the 7800x3d is more powerful and gets hotter, so it requires better cooling. Apart from that you can combine things however you want.
For more actionable advice, we would need your budget and a list of requirements (gaming / streaming / video renders / etc)
It’s gonna be a while before RISC-V (and the accompanying software) is ready for consumers, but this is a great step towards that goal. Framework is the perfect development plattform, due to the modularity.
I’m super excited about this, didn’t expect it to happen so soon.