Which is why I said "some boaters" -- who only have a solid-fuel stove, can't easily fit a gas or diesel boiler, or simply can't afford to both fit and run one. Electricity used for heating is *very* expensive unless it runs a heat pump, just like for houses -- unfortunately right now there doesn't seem to be a good heat-pump solution that can be easily fitted to narrowboats.
So it's not always easy for everyone to switch, even if it would be desirable from the emissions/smoke point of view. However the "vanity" pollution emitters -- which includes "lifestyle" woodburners in CH houses and Chelsea Tractor drivers, very often the same people -- have no such excuse, they're adding to the problem purely out of choice.
(farmers or people who live in the middle of nowhere and *need* a 4x4 are excused, but don't forget that something like 90% of them are in towns and cities and never go offroad -- unless you count parking on the pavement outside Tarquin's school...)