I’m quite the opposite, I feel like MDN is the only sane resource in an ocean of opinionated crap. Not saying it covers everything but for syntax it’s practically the only place I visit.

Same here. For syntax and quick examples, I find w3schools much harder to parse than MDN. Maybe there's more noise in w3schools, or maybe the layout/design of MDN are better for these purposes.

But going to w3schools is like trying to kill a fly with a flyswatter with a dashed red border of weight 2px. Their examples are so basic, pre-canned, and repetitious between pages that you rarely see useful options and intricacies that each tag/property may posses.

For super quick syntax checks ("Is it fill-opacity or opacity?") MDN might be a little overboard, but as any sort of reference beyond 3 line snippets it is the link that I always look for. I usually append MDN to the end of my searches for HTML/SVG help.