I actually find it a lot harder to convert content to new figures than to use the weightmapped versions of older ones.

Of course, that's because other people have created the weightmapped versions for me. But once you have those installed, adjusting clothing is easy. I just copy joint zones. The results, IME, are much better than converting clothing to other figures. Morphs and textures don't need to be converted.

If I had more skills, it might be different, but as it is...converting clothing really doesn't work well for me. Even with helpers like Wardrobe Wizard or Crossdresser, the results generally don't look that great.

And converting textures is a huge headache. With a weightmapped  version of an older figure, you can still use all the characters created for the older figure. Those can't easily be converted to a new figure.