The current iMac (if you spec it up) has a 9900K in it, which is a 9th gen (i.e., current-gen) CPU. The 15" MacBook Pro has 9750H/9880H/9980HK CPUs, which are again bang up-to-date current-gen CPUs.
Maybe back in the 90s they were slow, but these days Apple uses bang up-to-date CPU hardware...