I don't think she was doing for "evil lulz" but it was clearly an attack, the government developed the "Ridley Plan" some years before to prevent and curtail the power of organised labour in the UK. The motivation for this was the capitulation of the Heath Government to the NUM in 1972 and the fear of the use of strike action as a military weapon by the Soviet Union - the British Unions had extensive ties to the Soviets. The industry wasn't uneconomic but the installation and development of subsidized oil and nuclear plants and the willingness of the British to import coal made uncompetitive. There was a prospect of another 50 or 70 years of deepmined coal for Britain - a highly undesirable prospect, but there is an alternative universe in which the NUM won and we would be trying to deal with this now.

"The UK has identified hard coal resources of 3 910 million tonnes, although total resources could be as large as 187 billion tonnes."

https://euracoal.eu/info/country-profiles/united-kingdom/

And occam's razor states "the simplest theory that fits the evidence" there is extensive evidence that the UK has large reserves of coal and could have continued to exploit them for many decades. However, for political reasons it didn't.