Yes, but those 'welfare states' didn't come into existence overnight, or with a doubling of taxation in one year.
They were built mostly incrementally over 3 decades with the occasional leap forward.
With 20% VAT we could deliver many of the rewards you would like. But no one is going to run on, or deliver that in the next term of government.
To get to 20%, you need to start by getting to 14%.
At any rate, lets not get too distracted by fantasies, we should compare real options on the table, not imaginary ones.