Keep in mind that if you use MDUW+ for lots of layering, well, Rytm does that too.

8 voices looks small on paper, but you’ve got a synth/sample layer on each. So with a little parameter locking, you have 16 sounds. This does not include the 4 tracks with their own parameters, and synth/sample layers that are on the other sides of choke groups, nor does it include sound locks on all 12 tracks. I’ve never run out of voices on Rytm, and I do entire songs on it.

I wouldn’t call the Rytm limited compared to MDUW+, but rather just different in its limitations.
Rytm has loads of unique features, as does MDUW+.
Both machines are exceptional, and neither can truly replace the other. Elektron was very clever about that.