Rant: My calathea is a victim of online plant forum chaos

I noticed my calathea's leaves curling up, so I checked a popular plant care forum for tips. One person insisted it needed a pebble tray for humidity, so I set that up. Another user swore it was a watering problem and told me to only use distilled water. Then a third comment said it was root bound and needed a bigger pot immediately. After following all this advice, my plant looks worse than ever, with yellow spots everywhere. It's so annoying how everyone acts like an expert but gives totally different fixes. I just wanted a simple answer, not a dozen confusing steps. Now I'm scared to even look at another plant forum for help.