That’s total nonsense. Immigration is the bigger issue. Economic policies can be adjusted relatively easily.
You also need to understand that the people in France willing to vote for the FN are mostly poor and working class people who will not vote for a party that wants to slash pensions and favor bosses over workers.
The rich people who want to have less government spending refuse to vote FN no matter what, so why would the FN pander to them?
The FN in the 80’s had Thatcher style economic policies, but they couldn’t get many votes. They became a player after embracing economic populism. Same with Trump here. A lot of conservatives are in denial about this, but Trump ran against the typical conservative positions on economic issues. Trump said he will preserve the social security system and made positive comments about government provided healthcare in the debates.
No it’s not.