E-Z lube axles

There are automotive quality bearings available. Having built equipment trailers on and off for close to 40 years, I prefer to use quality American bearings and hand pack the bearings when necessary. I don't get overly concerned about doing it every year, but I didn't do it every year on my cars or trucks before they had sealed bearing packs either.
I don't have an issue with using the easy lube spindles if done properly. Just don't rely on them keeping you from servicing your bearings every couple of years, depending on usage.
Trailer bearings service isn't magic.