No, that isn't accurate. Air to water heat pump systems can be incredibly efficient and effective, even if the insulation isn't great. Flow temperatures are usually lower than gas boilers, so sometimes radiators need to be upgraded to larger ones but with a good quality heat pump and proper setup (weather compensation being a big one) there actually are few problems.

There is a huge education gap unfortunately, since there are grants to install them so you get dodgy installers doing crap jobs. Even with a high quality heat pump, if it's not set up correctly you can get COPs as low as 2.5 or so and pay more than having gas. There are some good channels on YouTube of people with the proper training making fairly minor changes to these systems and acheiving SCOPs around 4 which is cheaper than gas.