Length can absolutely weigh down curls. When I had about six inches more length than I do now, it was depressing. Went from 3b/c to mostly 3a w/some 3b. Not that I dislike that look for others, just like curlier hair better. All that length even caused headaches for me
Plus, I got sick of combing through all that length.
Layers, as other suggest, can really help! You can have your cake and eat it too because you can keep your longest layer/s long but just have the shorter layers to bring back your curls (ultimately I let go of the longest hair too out of laziness). Also, it makes it easier to finger comb - you spend less time because you really do have less hair on your head