Paying a tax on something you import from the EU which you don't pay if you buy in country is difficult to see as anything other than an import tax, no matter how it is named. See VRT in Ireland for example.
VRT is paid whether you buy a new vehicle from a manufacturer in Ireland or elsewhere in the EU. It's also paid if you buy a new vehicle from outside the EU, but in that case there will additionally be import taxes.
It might be that the administration is different (e.g. the large vehicle importer usually pays it, but you pay it yourself if you're buying some exotic Lotus direct from Britain).
It might be that the administration is different (e.g. the large vehicle importer usually pays it, but you pay it yourself if you're buying some exotic Lotus direct from Britain).