I have learned as I progress on my guitar journey that there are no hard rights and wrongs. It is what works for you. “Guitar people” especially social media types like to say if you play this song like this, you are doing it wrong, “only do it like this”. I like to reference a couple of pretty accomplished guitarist. Zack Wylde said that every one of the guitarist for Ozzy played the songs differently, from how they fingered the notes and chords to what position of the fretboard they played them in and none of them were wrong because they all played the songs and people knew what they were playing. Alex Lifeson said in an interview that he watches different ways that people play his songs on YouTube and some are actually better than how he plays them. As for muting the low E string, I have found that different situations call for different muting styles. I find that most of the time I will mute an open C chord with the tip of my ring finger and for an open D, I use my thumb. I was doing one of Anders courses years ago and found that it was easier for me to finger a piece differently than he did. I went to the forum and asked him about both ways and if I needed to do it his way for something in the future that I didn’t know that I didn’t know yet. He basically said try both and do what works for you.