Could it work?

How could it not??

How would this be possible? How would an individual employed by a company withhold tax from their wages, if they’re paid net? Surely it would need 100,000 self-employed or businesses themselves to withhold tax from HMRC?

Let me remind you that a government doesn't need to tax in order to spend. Spending comes before taxing.

"Let's financially cripple our country and build a giant virtue signal in the process!"