I'm sorry but your comment and the post you link to is complete nonsense economically and worse applied to Keynes and Friedman is utterly wrong. The article you linked is an honestly an embarrassment.
Furthermore nothing in the actual economics of either of these two people puts them squarely in the supply-side/demand-side 'camp' and furthermore those terms are used competently wrongly to the point of meaninglessness in public discussion anyway.
I don't want to get into a long post here, but your way oversimplifying the issue economist discuss to a point where it borders on satire.
To get a somewhat better understanding in a short time:
Furthermore nothing in the actual economics of either of these two people puts them squarely in the supply-side/demand-side 'camp' and furthermore those terms are used competently wrongly to the point of meaninglessness in public discussion anyway.
I don't want to get into a long post here, but your way oversimplifying the issue economist discuss to a point where it borders on satire.
To get a somewhat better understanding in a short time:
- https://www.econlib.org/library/Enc/KeynesianEconomics.html (written by Alan S. Blinder)
If you are further interested in the history of economists long dead, consider:
- https://www.mruniversity.com/courses/great-economists-classi...