Yup. Probably because law enforcement would be livid if Apple did that. In the San Bernardino terrorist case, Apple basically said triggering an iCloud backup is the best way to get the contents of a locked iPhone. Apple routinely supplies law enforcement with contents of iCloud backup.
It remains one of the clearest examples of law enforcement wanting a friction-free solution for getting data out of iOS without Apple. They could have easily attained the information and have been doing so for years. They were explicitly trying to generate sympathy towards a backdoor solution.
What's sort of surprising to me is how much they overestimated public support for their cause.
There are plenty of non-LE use cases, such as people who need to recover access after a lost password, as well as families who want access to a deceased family member's information after the fact.
Apple has been (slowly) adding support for other recovery systems and for legacy contacts as first-class features. The UX for this currently lists Apple as a fixed option among a list of other options (such as personal contacts).
I expect long-term that Apple will have access to backup recovery for a number of people as a system default, but not for everyone.
E2EE would have made it significantly harder for Apple to build the web based apps at iCloud.com. Not to say that shouldn’t have though, but I can understand whey they didn’t.
I think the main thing is Find My access, but Apple seems to claim it's E2EE despite being available at icloud.com/find so perhaps it wasn't too complicated; I imagine it stores the plaintext password in memory to access the data.