Agree with your take. Recently helped install a heat pump at a single-family home (rental property) in the SF Bay Area. Actually, they aren't that much more expensive than AC's (mine cost about $9k for everything, but again, I did 35% of the work myself for a ducted 3 ton heat pump). And yeah, the installation is almost exactly the same as what you'd do for an AC.

And, you don't need to add insulation, but we did (to the crawlspace), costing about $2.5k

And, it's been running for about 3 months, and saved about ~$175/month in heating. wow. It'll pay for itself in about 7-8 years.