There are more on updates on Android than "oh it gets x years of updates."
First, there's the Android version upgrade. Most Android phones would get at least one major version upgrade. Only Pixel and Samsung that promised 3 years of upgrades. The rest like Oppo, Vivo, etc are so inconsistent that most of their mid-rangers and lower don't even get a single version upgrade. (this is why I balked when these companies are trying to charge $1000 for their flagships. Complete waste of money as they have zero track on software support).
Then there's monthly security patches. Google send these monthly patches to OEMs 1 month in advance very month. Again, Pixel and Samsung lead the way. But for Samsung, it's not the complete story. Only their flagship lineups (S series, Fold series, Note series) get the security patches monthly, with few exceptions on models that has enterprise ready status. The rest of the lineup, even the premium A7x series, only get the security patches quarterly. To me this is unacceptable since Google has made it so easy to apply these patches. Security patches are that, security patches. There should not be any reason to not apply them in a timely manner. This is why I decided to go all the way, traded in my A71 to an S21. As for the Chinese, they are inconsistent. Many do give security patches, but there's almost no pattern to it.
Oh and for Samsung promising 4 years of security patches? Cross that out. Just read it as 3 years of security patches. Why? The 4th year is biannual delivery, meaning you will only get 2 security patches in 1 year. That's just BS. It's better than nothing, sure, but again, Google has made it so simple to apply these. It's so easy that some OEMs were caught that they just changed the text to fool users into thinking they have the latest security patches, without actually applying the patch. These attitude towards security is inexcusable imo.
In short, best of the best on Android are still Google Pixel and Samsung with 3 years of software updates. Still a far cry from Apple, obviously. This is also a reminder whenever the likes of Oppo or Vivo are trying to sell their phones for $1000 (Oppo Find X3 Pro is about $1100 in my country). No way jose. Paying $1000 for only 1 year of software support at best is ridiculous. Might as well get an iPhone if you have that kind of money.