In all seriousness, I forget my wallet more often than someone my age should. Keeping an extra couple of twenties in my car has stopped that from ever once being a problem. I've never felt the need to have a payment option on my phone or smartwatch, let alone implanted in my arm. What happens when you decide to change banks?
And beyond that, you admit to having a minor need this could address. Can you understand that for others that same need is much larger due to other circumstances?
It's impossible for an implant to be 0 risk.
Removal is more complicated than implanting.
You can't change the data on it, so if you get skimmed you need a new implant.
However if it is re-writable (some are) you'll need to know someone/buy expensive specialized hardware.
I say all the above as someone with a magnet implant in my finger for the past 6 years. I still love having done it. But for practical uses like payment systems in an implant sounds like a horrible idea. (https://en.wikipedia.org/wiki/Magnetic_implant)
If it's basically an NFC tag, can't you make it read-write? Or is this potentially doing something more than that?
Also, how did you get the magnet implanted? Despite having no use for it myself, I still kinda want one.
That's easy. Just swipe your smartphone over someone's arm until it beeps, then use your fingers (or phone's flashlight) to find it. Shouldn't take more than 3 seconds.
You can't lose it.
You can't forget it.
You don't need to charge it.