My pothos dropped 30 leaves in one week and it came down to a $3 fix

My golden pothos sat in the same corner of my apartment in Chicago for almost two years and grew like crazy, then two weeks ago it started dropping leaves. I lost maybe 30 of them in seven days, and I panicked and did everything wrong at first. I moved it to a brighter window, gave it more water, and even bought a bottle of fertilizer, which made the yellowing worse. Then I finally pulled the pot out of its decorative ceramic cachepot and found the real problem. The cachepot had no drainage hole and about an inch of standing water sitting at the bottom, so the roots had been rotting slowly since winter. I dumped the water, switched to a plastic nursery pot with holes, and stopped watering on a schedule, only when the top two inches of soil feel dry. Three weeks in, there are four new leaves unfurling and no more yellowing. Has anyone else killed a plant with a pretty pot that had no hole in it?