I am tech savvy and I’ve never heard of SMR or CMR. After reading up on it, I don’t think it really matters. SMR is newer technology, and is maybe more reliable in the short term, but the drives fail faster because of the extra wear and tear, and the drives are slower than CMR.

https://history-computer.com/smr-vs-cmr-hard-drives/

Edit: I missed that SMR is supposed to be worse, despite being newer. So I guess WD is putting slower and sooner failing drives out to save a buck.