Define „better“. Otherwise it makes no sense.
They both are taken from real games, therefore the positions are real. Both adjust the puzzle rating based on success/failure of solvers. From what I can tell, both are basically the same.
chess.com included many studies, I recognized many.
Lichess tactics are far better because they didn't rip-off this planet's most valuable chess resource, that was making chess free for everyone, in order to charge a premium on it.