Ummm... Cristiano carried the attack, true - but his exit wasn't the end-all for the attack. Jovic has been a disaster and so has Hazard, but the team still has the potential to score goals. Cristiano was always going to be a loss, but Benzema stepped up and arguably, with Vini maturing, if Hazard and Jovic had been even competent professionals and no more, the attack would be fine. In defence, it's a different story.
Ramos isn't just the captain and the best CB at the club. He is the driving force, much more than Cristiano ever was. He holds the back line together, drives forward and also chips in with crucial goals at the other end. He was the second-highest scorer last season. Sure, that includes penalties, but they're important goals and show his cojones. Look at the Real Madrid record with and without Ramos and you start to understand his importance and impact. Don't think the comparable analysis for the team with and without Cristiano was ever this stark.
He won't be sacked. The Madrid fan base will always have a vocal element asking for change - but let's not forget that a sizable number even wanted Mourinho re-appointed. Zidane will stay.
"Carrying the attack" is no small part of the team, and even though in theory, others should step up, they lost pretty much exactly his goal/assist contribution each season.
Benzema was good in the last two seasons, but he didnt really "step up" as much as he returned to normal level, people forget, before the 16/17 and 17/18 seasons, Benzema scoring around 30 a season was completely normal(his statistical best was with Ronaldo, btw).
RM are not done as a top club, but they did lose a lot of firepower, and fear-factor with Ronaldo leaving, which is shown to full effect in CL, where they just aren`t a contender anymore, a lot of that has to do with Ronaldo leaving(though not completely).
Ramos, on the other hand, carries the defense(while contributing with key goals), and im well aware of their record without Ramos, he is incredibly important, and i do put him around the same level of influence as CR, Varane doesnt know what to do when Ramos isnt there.
There is a direct comparison to be made i believe btw, RM crumbled when Ronaldo was in bad form in la liga 17/18, no one else stepped up.
Sure, "bad form" vs "Not playing" isnt exactly the same, but there is still says something.