The UK CAA, and I believe any other European CAA, does not mandate ATC sitting in the tower of the IAP destination airport.
And conversely, the FAA
does mandate approach control, but as you say, the ATC is provided remotely. There's no real difference, apart from the willingness of the taxpayer to pay for it.
In France, IAPs to unmanned fields are routine, with a remote approach control (often seems to be the SIV).
In Germany, at class F fields, approach is remotely provided but an AFIS is required on the field as well.