It depends on what you are doing, in short it’s not necessarily harder to play, but you do end up doing some homework to prepare to play something in DGCF that wasn’t originally written that way (no big deal, part of the joy of learning and practicing). Directly transposing up or down 2 frets is easy, and DGCF moves you up the neck to smaller fret size, i.e. like a 30” short-scale. Adapting open strings or shifting notes to other strings/octaves is trickier on the fly… takes some practice to re-arrange—each piece of music is different—absolutely feel free to choose a different octave for a note when you want to, like any other time you might transpose to a key that wasn’t the original tuning (make it your own!). One thing I do notice in DGCF, I tend to anchor more with my fretting index finger and I use my pinky more than when I use E standard or Eb 4-string, but that anchoring is similar to what I do sometimes on a 5-string anyway. I had to work to eliminate a technique problem with my pinky, (off time and overcompensating with too much force to land the pinky = bad note, drilling the right hand/left hand timing helped with that). Once your DGCF confidence is up and your instrument is set right for you, it’s fun—nice to have down to D, don’t have to do Drop D to get it, plus you can tune your setup to match whatever you’re doing that calls for DGCF.