The Turnbull government, which has championed innovation and tax breaks for start-ups as part of its "ideas boom", has found an unlikely critic: a billionaire tech founder.

Atlassian co-founder Mike Cannon-Brookes took to Twitter on Monday night to rail against comments made by politicians on the ABC's Q&A program.

Mr Cannon-Brookes, whose company is worth $8 billion and is held up as the Australian start-up success story, has previously called out companies that move to Singapore to lower their tax.

He said on Monday that no legitimate start-up saw paying taxes as a barrier to becoming a company.