Punctuating generalized statements that can't possibly be reflective of every Mercedes with a capitalized word cutting off debate strikes me as extremely condescending and pretty off-putting.
(slight thread derail, feel free to move if a better subforum or thread)
Having said that, I did rent a 2019 300GLC with around 35k miles this past week and its a nice vehicle. Contrary to your statements, there was no alcantara, leather or carbon fiber in sight. It did have a few odd noises I couldn't pin down but none were obnoxious and only manifested on really crappy roads, also being a rental I'm guessing they're not holding Mercedes feet to the fire to address. The stock stereo was completely awful at any speed above 10 mph, it did not have Apple carplay that I could tell (plugging into USB asked me to download some mercedes app, which I did not), and the cabin was just as loud as my 2022 MYP. The engine was okay in terms of pep and ability to get up to speed / pass, and generally scoot around but its no Tesla. Requiring premium fuel octane and returning 26mpg on nearly equal highway / local roads, the cost per mile was a solid "meh".
Is it a nicer cabin than the MYP? Yes but also no. The controls and dash are very busy, the lack of Carplay was a disappointment, the stereo is poor, the various menus and submenus were horribly confusing, unintuitive , and incomplete. The interior is generally no quieter than the Tesla. I also had a really hard time finding the goldilocks seat settings despite spending 10 mins a few mornings trying to dial it in. The climate control was also super weird and kept fogging up in the morning, requiring me to put defrost on high for several minutes even when it was 65f out, making the cabin uncomfortably warm.
Where it excelled is the ride, and a 300 GLC at $50k, closer to 60k when you load it up and fix some of the deficiencies in the base model (sunroof, driver assist features, vented seats, Burmeister sound) is a fairly reasonable value if you're shopping in that price tier. Last I looked (before getting a VIN on the MYP), they were really hard to find however, not sure if they've fixed their supply chain issues.
Would I pick it over the Tesla just for the interior? Not me, I was ready to move to BEV, Would I consider an equivalent BEV from Mercedes or another luxury brand in the future? Sure, but they seem to be aiming for the next price tier up. The MYP, while well within my financial means, was already uncomfortably expensive and felt like a total splurge.