Nerd! I train counting one one thousand, two one thousand, etc. I do use a length of rope to measure out my courses, is that a gadget?

The answer is, of course, "it depends": on your objectives, accumulated experience in the sport, and personal preference. Kind of silly to debate whether "more gadgetry" is better or worse for all situations.
If I'm doing interval training on the bike I personally need the PM to confirm that my PE is accurate ( I often drift below target if not paying attention), and to log weekly hours/stress. Do you need it on a long, easy ride? Probably not. Does everyone need it? Probably not.
Running I bring along just a watch just so I know how long I've been outside. Easy to calculate average pace if you know the mileage. Sometimes it is nice to have mile splits on tempo runs to gauge progress? Necessary? No.
Swimming - I wouldn't consider a pace clock a "gadget" but that's just because I've been swimming 25 out of the 32 years I've been alive. Impossible to do any structured set without one...

If you train without power on the bike then you had better be riding a shitty ass bike or else your money would be better spent on a power meter. Unless you don't care at all about getting better in which case why would you even be reading this forum to begin with. It isn't about being a slave to the power meter, it is about gauging progress on the bike which, without a power meter, is damned near impossible.

This thread is proof that white people with money and time on their hands can come up with some seriously stupid reasons for complicating every facet of their lives.

This thread is proof that white people with money and time on their hands can come up with some seriously stupid reasons for complicating every facet of their lives.