If self employed people have declared and paid full taxes on their earnings then they are entitled to help from the state, according to the chancellor. If they thought they didn't need to contribute their fair whack to society by taking cash in hand and not declaring all earnings then, no, they shouldn't be compensated by anyone, in my opinion.
Also, owners of private companies who are billionaires should not be claiming furlough off the state for their employers; surely they can afford to give up the odd million or two for the relatively short time during lockdown. That could be their contribution to society for their own good fortune. It's possible that their accountants will have been taking every (legal, unfortunately) advantage of every loophole in the book to get them to their present state of wealth anyway. Or maybe they have become tax exiles; should the country help them when they left to avoid paying tax in the first place?
I'm all for people making their fortunes, lucky them, but only if they have been fair to their employees and customers who have made them wealthy.