You beat me to it on that last line, but I'll highlight some others [emphasis mine]:

Berry is even more pointed about his concerns in the convoy’s private Facebook group where he and others have shared graphics claiming “the World Health Organization and the United Nations are instructing elementary schools around the world to have pedophilia normalized.”

[…]

Phillips says Sager’s comments point to the influence of “sovereign citizen ideology.”

As soon as I saw the headline, I wondered if Romana Didulo would be mentioned. She's a conspiracy nutbag who declared herself the Queen of Canada and started her cult of followers caravanning back and forth throughout Canada. She's been active since 2020. There's a fascinating look at her org at Vice. She wasn't mentioned in the original article, however.

I can "understand" what they dislike about everything here except for ... math? Like, what? What could anyone possibly have against math?

Got keep them safe from Big Pythagoras

He learned they were teaching Arabic numerals and now he's afraid of al gebra.

It’s about time someone stood up to math.

If god wanted us to count past ten we’d have more fingers.

maybe they meant meth? or they've got a deep-seated fear of trigonometry?

It is of acute importance to stay vigilant of mathematicians; we cannot go on tangents and let their plots divide us. I'm sure they're integrating themselves into positions of power, and knowing even a fraction of their schemes could be of prime significance to factoring out their plans to subtract our freedoms.

PI IS EQUAL TO THREE!

I've got a math degree, can definitely say I felt like a victim at times

Could be this? https://www.cnn.com/2022/04/17/us/florida-math-textbooks-critical-race-theory

“ DeSantis said state officials “got rid” of Common Core, a standardized teaching method rolled out in 2010. The method requires children to group numbers to solve arithmetic problems, rather than the vertical “carry the one” method familiar to most adults. The approach goes beyond simple computation to emphasize deeper mathematical concepts. The department said some of the rejected textbooks incorporated Social and Emotional Learning (SEL) and references to critical race theory – two frameworks or philosophies that some conservative groups claim are being used to indoctrinate students. Some schools around the country have recently used SEL strategies to help students cope with stress and the impacts of the Covid-19 pandemic. The Collaborative for Academic, Social and Emotional Learning defines SEL as a teaching framework aimed at helping “young people and adults acquire and apply the knowledge, skills, and attitudes to develop healthy identities, manage emotions and achieve personal and collective goals, feel and show empathy for others, establish and maintain supportive relationships, and make responsible and caring decisions.” More than a dozen states have set standards for teaching SEL in grade schools, according to the National Conference of State Legislatures. But as more states consider SEL strategies, conservative groups have claimed critical race theory is embedded into the framework.”

They are already part of the "base" that Squinty McProudBoy is building.

If you consider 'Math' as a stand-in for 'Science' and 'empirical evidence' their fear of it becomes a little more cogent.

AKA projection. These types of people tend to have that in common.