Yeah, same - I tried the M5 Pro randomly while waiting for my daughter to finish salivating over a Neo, and just got surprised by how quickly it opened apps and reacted to anything I did - ~1-1.5 seconds for Affinity Designer was amazing.

My MBP probably got affected by OS updates like other people are saying - opening apps and responsiveness definitely got worse, and felt like slightly deteriorating over time (but it might have been MacOS updates along the way).