Given that SMR drives suffer from abysmal random write performance, which is a key type of write pattern that impacts performance in desktop operating systems, the drives will result in noticeably slower performance for PC users.
Really though, random write performance has always been pretty abysmal for mechanical hard drives, and this is just worse. However, we have been getting to the point where most system these days tend to be shipping with an SSD boot drive, and for bulk data storage the performance of these drives should be reasonable. I guess they could potentially be problematic for someone wanting to install an extended game library to a hard drive though, and some RAID setups seem to have problems with them.
Obviously, the use of SMR should be indicated, and not just randomly substituted into existing drives. Hard drive companies have been doing similar things for years though, cutting corners on existing models of drives, changing platter counts and so on, without really providing any indication of such changes. The changes made here can have a bigger impact on performance though.