$ time curl -L 'https://codeberg.org/'
real 0m3.063s
user 0m0.060s
sys 0m0.044s
$ time curl -L 'https://github.com/'
real 0m1.357s
user 0m0.077s
sys 0m0.096s
That depends on location and GitHub pages generally take a while to execute all the javascript for a usable page even after the html is fetched while pages on Codeberg require much less javascript to be usable and are quite usable even without javascript.
Here are my results for what it's worth
$ time curl -o /dev/null -s -L 'https://codeberg.org'
real 0m0.907s
user 0m0.027s
sys 0m0.009s
$ time curl -o /dev/null -s -L 'https://github.com/'
real 0m0.514s
user 0m0.028s
sys 0m0.016s
Here are my results for what it's worth