The low speed writing thing is not really a thing any more.
Back when we did not have nice inks in the CDs (or if you did it cost a fortune), the drives did not have much in the way of buffers and hard drives might also have been slow enough if fragmented and doing other things that it could be slower than they could write.
None of those really apply today. About the worst I can say is some of the combi drives today that do DVDs as well are not as fast as some of the later stage CD burning drives. Indeed if they even can write at 1x/2x it might not be ideal for them to do.