It's important to understand what this means technically.
Android has been weak about supporting true end-to-end encryption. The reason being they don't control the phones and so they have limited ability to ensure/force the appropriate hardware security chips. Apple on the other hand does and they have steadily increased their phone security over the years which has sometimes got them criticized for doing things like requiring fingerprint sensors to be changed only by Apple Stores. Android could never do something like this across the Android ecosystem.
It is clear that law enforcement can subpoena any datacenter data they want. And if it's encrypted on the cloud they can also compel cloud provider to decrypt it because the provider refusing to decrypt data that they know how to decrypt would simply be obstruction or contempt. And the provider can't stand on any legal principle that the user has a right to privacy because law enforcement already has a warrant authorizing them to have the data.
Also there have been recent scandals about cloud platform employees, whether phones or cloud security camera companies or whatever, accessing and leaking cloud data, which despite whatever "controls" in place is possible in principle through various leak potentials that exist even if the data is "encrypted".
Apple seems to actually care something about user privacy, as long as it's aligned with shareholder value which it plausibly is if it helps them sell more iPhones. So the workaround to this cloud data security problem is true end-to-end encryption, where apple doesn't have the ability to decrypt the information at all, because the encryption keys belong to the user only. A system where Apple has no idea what the data is, and couldn't provide it to LE if they wanted to, because the private encryption key is held by the user on his phone, which has to be located and cracked, if that's possible to do without destroying the keys. It's common for security microprocessors to hold the private keys in volatile memory which can be automatically flushed on command in any attempt to recover the keys. I used to work for a company that made such processors and they have thought about lots and lots of potential attacks and errors, even obscure ones only used by sophisticated attackers who have the ability to disassemble the chip. So even probing to hardware itself can be hard, besides the fact that making LE have to physically locate the phone and crack it is already a huge (security benefit for user = hindrance to LE) vs. LE just sending an email with a rubber stamped warrant to Apple, which through FOIA requests, we know they do hundreds of times per year.