I disagree, what's the stat on the top X% of workers contribute the Y% of all taxation stat? Richard Branson could donate loads of money to the government and ask for it to be ringfenced to the NHS. So could a lot of rich people, they don't do it though. Instead they campaign for a new tax enforced in law and meanwhile they'll stash a load of money in overseas tax havens. This is purely a publicity stunt to make it seem like he gives a ****. When in reality he doesn't, because if he did he'd just do voluntary taxation.
If all the people in the country who agreed income tax should be raised and that say "I'd happily pay more tax" actually willingly gave more tax, I wonder how much of a difference it would make.