Western capitalism is dying and more people than in a long time are starting to question it. But if Reaganomics hadn't come along, if everything hadn't been deregulated, if taxes on the mega-rich had been kept at a smart level and most people were somewhat comfortable. Would capitalism be crumbling as it is now?
What if Reaganomics coming along and emphasising everything bad about capitalism ends up being the start of what causes everyone to lose faith in it?
To some extent the shift towards neoliberal ideology and by extention economics was a nessesity due to a falling rate of profit due to a recovering Europe post ww2 as dead labor would build up again. I think fundamentaly the left as a project has had Critical issues with with providing workers with any real glimpse of a better future so they end up falling into reaction or getting gifted by suck dems. The problem extents into now better time then ever to start a unionization drive but workers are doing this without us. To more directly answer your question reagnoics and thatcherism had to happen to some extent when it did due to profit rates falling and capital literally needing to squeeze blood from stone.