No, hire car, not a taxi. You really don't need to book months in advance to get one, unless you live somewhere with unusually high demand for them. Most places you van get same day.

PHEV emissions are only lower if you use the battery, majority of phev owners don't even charge regularly. With the majority of miles on the ice ruins any gains on emissions. Emissions are only one part of the impact to the environment, brand new cars even evs have a higher initial impact that reusing an old car, especially one no-one will want in a few years.

Car weight is also a factor due to brake and tyre wear, and guess what, a phev is carrying around all the components of an ice and all the components of an small ev, way heavier than the old car, even ignoring that modern cars weigh more anyway...

It's just such an unlikely set of requirements the number of people that actually meet it is pathetically small.

All of these have to be true for your example to make any sense: Commute distance less than the battery range, typically just under 30 miles

Able and prepared to charge every night as that commute has just drained the tiny battery, another poster has already pointed out that the majority of PHEV owners don't actually charge

Cannot plan any long trips greater than 400 miles

Lives with no reliable hire car service

Lives more than 400 miles from a public ev charger

Somehow can do more miles a year to save money over buying an older, cheaper car that's about £15k cheaper to buy

It's just comes across as a bad faith argument, sorry.