That's exactly the way it works for me too. I bought a PHEV when I retired in 2020, as I could predict making a lot more short local trips that my existing diesel was ill suited to. I did keep it below £40k, and I didn't bother with a home charger as there was already a suitably located 13A outlet and the 4 hour charge time has never been a problem. I'm used to managing the choice of power source during longer journeys to maximise mpg and to have electric charge available for areas where it's most beneficial.
Re the tax, AIUI this is the "benefit in kind" assessment of the taxable income that a company provided vehicle is equivalent to. PHEVs were assessed at a lower tax rate, but there was no check on how suitable they were for the intended use, nor monitoring of how they were used. So some people got PHEVs for the lower tax, but used them effectively just as petrol cars.