Swimming against the tide
So people want to fix their own phones, huh? No, they don't. If they did, they would do a quick search on a well-known Internet video site, see how easy most jobs are already... and then do it.
Seriously, replacing the screen or battery on most phones is already do-able for about £20. I've done about 15 fixes for friends and family. Every time I advise them that I provide no warranty - it might work after it's passed through my hands and it might not. Every time the device has been like new after the fix apart from one iPhone 6 which needed a new front-facing camera... which cost £2 off a well-known Internet auction site and was easy to fit.
I suspect that what people want is for it to be cheaper, easier and quicker to get someone else to do it for them. That is the modern way, sadly.