You should understand that with Ronaldo in the side it forces teams to dedicate very significant effort to shutting him down. Same deal with Messi.
When a team shuts down Ronaldo by marking him out of the game, sometimes with multiple players, it opens up a large amount of space for the rest of the team.
It’s basically a scenario of shut down Ronaldo and force the team to beat you... or treat Ronaldo like any other attacker, and focus on shutting down the team as a whole and hope he doesn’t beat you.
No one figured that out, how to shut down both Ronaldo and the team, in CL the past 3 years.
And it’s quite obvious how much easier Madrid is to shut down now, without him.