Hello Nick,
if really ' Firmware' is meant, as far as i know only Samsung has a FOTA-Offering. If Android-OS-Update Mangement in general is meant it gets more configurable (but that doesn`t help much, if the vendor does not offer updates) but the most streamlined experience you´ll get with Google-Devices like the Pixel-Series. Starting with them being the only ones offering Updates on a monthly basis and OS-Updates for minimum three years. After that comes nothing and after a while you might consider at least Devices from the ' Android ONE' list combined with ' Android Enterprise Recommended' . But the user-experience may (for sure) ' vary from vendor to vendor' .
Android One deals with many vendors re-inventing the Email, Contacts and Calendar-App plus Bloatware instead of using the Google-Standards. So it least, that's getting near to almost ' native' .
Updating Apps in Work-Management/Work-Profile without user-interaction is no problem and works pretty much automatically as they are managed via a single Android Enterprise Google-Account you setup within the console in the first place. So ' Auto-Update' is the standard behaviour.
Personally, if I see a Pixel-Device running with Work Profile, it is a very clean, intuitive experience and I would prefer it over every other vendor. On an Huawei it looks like...even if the device is on the Android Enterprise Recommended List. Not even Samsung comes near in my opinion. So in a nutshell: Work Profile is API-Driven within the Android-OS, that makes is comparable on the feaure-checklist (still depending on the OS-Version, not the vendor itself), but the outcome looks different from vendor to vendor. So get a streamlined experience, sticking with one vendor is from my point of view still the fist step to go.
In BYOD-Scenarios (as long as its Apple!), I would prefer clearly Apple. Added with User-Based Enrollment from iOS13 on.
