Possibly an unpopular opinion, but I don't think you need to go crazy with cleaning/trashing/burning your stuff. Spores are always floating around in the air, but they need the right conditions to geminate and grow.
Botrytis (aka bud rot) doesn't just need high humidity, it requires freestanding water on the leaf surface to germinate. Outside, this happens all the time from rain and morning dew. Indoors, unless you're spraying your plants with something, it comes from condensation.
Humidity is important, but airflow is really the key to prevention. Condensation can happen in two situations:
Rapid humidity/temperature swings, like when your lights turn off, the temperature rapidly drops and the relative humidity spikes (see "dew point", and why liquid water forms on the outside of a glass). Keeping the humidity stable is just as important as keeping it low. If you increase your exhaust speed/rate at which the air is exchanged into/out of the tent, it will keep your humidity more constant.
Poor airflow around/through the plant. The leaves and buds are constantly transpiring water vapor, increasing the relative humidity inside the buds themselves, and you need to move that humid air away from the buds before it condenses. This is what the circulation fans in the tent are for, so make sure there is air movement everywhere and no dead spots.
All that being said, as others mentioned some strains and phenotypes are just more prone to mold than others. I think it's partly down to natural immunity, like at a cellular level they can resist pathogens better, and partly the structure of the buds allowing more or less air penetration and condensation buildup.
Hope some of that helps you. Good luck!