Earlier quoted context omitted.
In my state they require: >160 hours of education/vocational training and 2 years’ verifiable experience in the trade To get the license to install minisplits (two years experience generally means working an apprenticeship). It's no wonder install costs are so much in the US. And as you've experienced, they're hardly rocket science to install. The 160 hours training would be more than enough, I'm not sure why 2 years…
Thankfully, the training is only required if you're doing the installs for/as a business.
And in my state, I copy pasted what was required for a 'residential' HVAC license (idk if you meant commercial HVAC or just making money on installs).