The recent TDZ rides have shown that it is too demanding of the client to render all riders/graphics when the group is huge. Real minimum hardware requirements right now are the same as for a gaming PC. I think that is too much to require for a training app like Zwift. It will exclude too many users.
It would be nice if Zwift can automatically adjust the graphics/demand on the PC so that the user will get a decent FPS regardless of the hardware on the client. The current minimum hardware requirements should still apply off course.
I think most users will rather have crappy graphics for some of these massive rides than to not be able to ride them at all.