I think a lot of it is how crappy a lot of new stuff is. Things seem to break a lot quicker.
It was just a slow drip but was only going to get worse.
My last water heater started to slowly drip from the bottom drain valve. Those can be replaced but the water heater was 15 years old so time for a new one anyway. Corrosion would have definitely been a problem if I tried.
The water here used to be very hard but we changed from township wells to city water and a lot better now. We had little choice since the city dug some deeper wells in the same area and were draining the aquifer.