A couple of points as I used to share your opinion, but I recently purchase a Edge Plus which changed my views (which while not as extreme were aligned with yours.

1.) For the most part, I do prefer stock android in terms of aesthetics and some key apps (dialer, etc).

2.) Samsung has really toned down their over the top "colourful" aesthetic on phones. They are increasingly following Material design guidelines.

3.) Depending on the carrier variant (and this could be killer), Samsung bundle apps are not as critical anymore and they definitely do not cause weird breakages when disabled.

4.) Having used both a Nexus 6P (considered the cream of the crop when it comes to stock Android experience) and there is very little performance difference between the two.

5.) Samsung (and other OEMs) have always been ahead of the curve of stock android when it comes to features that were co-opted into later versions on Android. They were the first to have quick access toggles in the notification bar, lock screen notifications, etc. So there were always some trade-offs.

6.) Even without getting into third party launchers, etc that can completely ape stock android in looks - Samsung has finally included proper theming support for their devices - so even a novice user can download a "Material Dark / Material Light" theme.

One perfect example that is still relevant to this day is the multi-window option that I use daily on my Edge Plus, which would not be possible on a Nexus device (just yet).

Their modifications are also a large source of their delay to update to new Android versions. It's somewhat ironic that many users buy their hardware despite their software modifications.