They are probably hyper-aware that they are on the precipice of a major PR disaster. Canadian police absolutely have the highly militarized equipment like BearCat armoured cars and such. They're not deploying it (yet). The heavier shit is lingering in reserve. That clip with a woman showing the police convoy on the highway counting vehicles mentions some of them being SWAT.
The last thing the RCMP wants is to be perceived by the Canadian public as evil oppressors gunning down good citizens. If they just came in heavy immediately, not only would it be a PR disaster in itself for the Coutts situation, but could be a flashpoint for major civil strife across the country, considering everything else that's going on. They don't want to spark outrage, it's already a powder keg.