After installing papirus-icon-theme my profile build became much slower, and after a few more generations I ran out of Inodes. After probing around with du I found that each profile had nearly 1.5M Inodes.

From 'du --inodes -d 1 /gnu/store | sort -n'

427406    /gnu/store/7038q3mds728lps7vrmn5ii4hzym4bs3-profile
1427426    /gnu/store/bkj5cqbq8r1kbh34w06548c6zhkf7f37-profile
1427440    /gnu/store/wjw3d19nyi838adf1gbx34yg00gws4ym-profile
1427449    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile
10900648    /gnu/store

And then further in the culprit:

19    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/hicolor
279659    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/ePapirus-Dark
279663    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/ePapirus
288689    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/Papirus
288689    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/Papirus-Dark
288689    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/Papirus-Light
1425409    /gnu/store/nxks5r9xg62av8c9harkcyk5x9ig45ka-profile/share/icons/

Here is my guix describe

Generation 2 Feb 04 2023 19:09:15 (current)
guix f57e20d
repository URL: https://git.savannah.gnu.org/git/guix.git
branch: master commit: f57e20d7289911a3691f089603c47cfdb828ea44