Ever since my partner bought her iPhone 6S on launch day, it has received four or five software updates - I can't remember but it was at least once a month.
On the other hand, the last update on my Samsung Galaxy S6 was way way back in October. Meaning, not only is Samsung's so called flagship still running on the archaic Android 5.1, the security patch for it is October! The mind boggles on why this company still loves treating their customers with utter contempt. Even my five year old Windows 7 laptop is still getting its monthly security updates (and also a free Windows 10 update that I haven't applied yet), but not a barely year old flagship.
Android apologists will no doubt refer me to the Nexus series - which I did own for two years under the guise of the initially superb, but then deliberately neglected Nexus 5 phone. If there was a compelling new 5" Nexus phone running on updated hardware that isn't more expensive than the S6, then I would get it.