I've had it all my life. I'm 55. Mine is bearable and generally I don't notice it. Mine was caused by "glue ear" or more likely the operations to "cure it", which caused ear drum scarring and what not. I don't think that glue ear is a modern diagnosis anymore. Mind you doctors were only beginning to not advise people to smoke for their health in the early '70s.

I know what a variety of tinnitus is like (I've never known anything else) and I'm sure that other varieties can be horrendous. In my case time does not help.

Perhaps we ought to insist on a tinnitus spectrum, with multiple dimensions and some TLAs. I don't think that advice from a single data point is very helpful, or being charitable: annecdata. I'm glad it disappeared for OP.

Tinnitus ranges from, say, me (I'll live) through yourself (fuck! but I'll live) to committing suicide in despair at the extreme end.