Allegorical, but I have 2008 Mercedes C300 (W204). I purchased it in 2017 with 90k miles and I’m currently at 190k. It’s still my daily driver and overall I remain pretty happy with it.
The tl;dr of this car has been toyota-like reliability with maintenance/repairs being uncommon but more costly when they need to be done. I wouldn’t assume my experience is indicative of Mercedes overall.
I’m not a mechanic but I am an engineering technician and test driver in automotive T&V