Not as old as op but approaching 40 fairly shortly. Most programming tasks are a variation of the same problem, you realise it, accept it and then realise that

Not as old as op but approaching 40 fairly shortly. Most programming tasks are a variation of the same problem, you realise it, accept it and then realise that the way to write good software is to get decent at the building bit and then work on getting decent at all the other bits around it. Requirements gathering (aka talking to people and writing down/recoding what they say), testing (hitting things until bits fall off), reliability (making sure things don't break the same way twice), documentation (making sure the poor sod in after you has more to go on than you inherited). There is a tonne of variation in what the average dev has to do day to day (unless you are a "Here are the requirements, you can change nothing, implement this spec, never question it" dev - in which case I pity you) so the trick is to keep learning in multiple domains when one gets stale rotate to another, variety is as they say the spice of life.