Many topics in maths and engineering are very intuitive to pick without formal education. To understand Humanities requires discussion with others. Writing and getting feed back on a lot of essays, listening to and explaining ideas in seminars, testing out an idea in a lecture. It can take a decade to start to understand someone like Foucault. It's hard to find a community of specialised discussion outside of formal education. Just picking up humanities from a few youtube videos or whatever is what I am convinced has led us to the kind of unobjective activism that is reacted against so much recently.
This is why years ago I watched the humanities students struggle endlessly with their first year statistics unit. The incredibly simple, first year statistics unit.
Isn't that perfectly reasonable? If you have the means to study as a hobby, then you should be able to enjoy that. If you haven't yet got the means for that, then earn it and maybe your children can do an arts degree off the back of your engineer's salary or you can do it yourself when you retire. The whole point of the government subsidizing education is to create useful workers that give more back to society with their useful work. Not to indulge people's pseudo-intellectual pleasures.
It's not as if arts degrees make people somehow superior at understanding society and arts and culture. Those are things anybody can pick up even with no formal education. Understanding the scientific method, statistics and critical thinking would go further in making well rounded useful thinkers than knowing what some ancient person's opinion about his local society was or training to become an activist who refuses to allow themselves to think objectively.