Has the cost of building software dropped 90%?

I strongly agree. It may be even more than 90%. For example yesterday I was able to use lovable (and Claude code web) on my phone to build out an almost 1:1 replacement (for my purposes) for an expensive subscription based app for working out: https://strengthquest.lovable.app/

This is simply unimaginable level of productivity— in one day on my phone, I can essentially build and replace expensive software. Unreal days we are living in.