Will the new IoM Director of Civil Aviation just have a register to look after or will they be considering the bigger picture?
What would be the bigger picture?
I think people go "Irish" because of reduced corp tax (no doubt somebody will correct me here
).
As for the Russians, all kinds of reasons. Wealthy private owners sometimes do this for privacy - you don't want every tom disk and harry back home knowing you
own a particular piece of metal.
Safety (lack of) may appear to be an issue superficially but in fact under ICAO any State can inspect/ban any plane if it is poorly maintained.
An AOC (any AOC) is worth having for tax free fuel; no need to actually fly the proposed operation. You can get tax free
avgas in most of Europe with an AOC, and I gather (this is secondhand) that in some places you need an AOC to get tax free
avtur too.
Of course, for non-AOC owners, the key feature of a register is FAA acceptance, and if the register is in the EU then any DfT or EASA proposal to prevent foreign reg planes parking in Europe would fail. A great deal of money is to be made in this area alone.