You don't have to replace the sensor unless the TPMS light being on bothers you and you don't want to go with the black electrical tape fix. I had one of mine go out a few weeks ago, did some investigation and decided that I'm just going to continue checking my tire pressure myself like I have done for fifty years. I'll likely wait a couple of years until I need new tires and replace the sensors then. Doesn't make sense to me to spend $60+ bucks to replace something that I don't really need. YMMV
2014 EV Coupe 20,500 miles
2014 EV Cabriolet 19,000 miles
I priced TPMS sensors for my snow tire wheels two years ago and Discount Tire quoted $60/wheel. $240. Pricy but I decided to buy them anyway. When they were writing up the sale the total was $120. I asked if that was for all 4 of them. He said yes that the $120 is the discount price. I wasn't sure why they were discounted and didn't ask but thought I'd pass that along.