The trends in edge computing are:
* chips are shrinking
* costs are decreasing
* power is decreasing
Many sensors are the size of a grain of rice, and have sleep modes that let them use very little power. Conductive threads are easy to get and feel just like regular thread. There is some hobbyist activity around sewable circuit boards like https://www.sparkfun.com/lilypad_products
, but they're geared towards hobbyists and soldering guns and could probably be shrunken another order of magnitude.
To get there, there are a few technical hurdles to overcome:
* Power. Likely, you'll need a rechargable coin-cell battery somewhere on the piece of clothing. That can be wired to all the sensors (using conductive thread). Ideally, the thing could charge inductively on a pad that you have at your house.
* Preventing shorts. The conductive thread might need to be protected so it doesn't short if the cloth gets wet.
Once those problems are solved, then it's a matter of selecting the cheapest sensors. Tiny sensors like this can be as cheap as pennies.
Once the sensors are wired in, then you need to solve how to store and forward the data out of the piece of clothing. Likely, it would use Bluetooth LE.
After that, you have a lot of data and need to build a UI to display and analyze it.
Eventually, when there are millions of people using this, you would need machine learning models to make useful predictions using the data.