You'll never achieve the emission goals in the US and EU without an ECU. Even the UPS, Unit Pump System, engines need an ECU to control up to three injections and they were the first engines with pre- and post injections.. You'll not achieve this with mechanical stuff. Toyota considers itself as a global mobility provider. Thererfore they have to sense what particular markets needs and what the regulations allow. The engines of Toyota you speak of can't be sold everywhere in the world, but they are still produced for countries where they are needed, can be maintained and the regulations allow them.
If you want to have an "old" Land Cruiser HZJ imported into the EU it must come with a base technology that allows to upgrade them to EU regulations. Companys like Tom's Fahrzeugtechnik or Nestle (not the food company) import these cars and modify them (in Germany). However, even in the countries they are produced, like South Africa, the regulations get tight. It is possible, that these good old engines will disappear, as well.
I personaly like the engines from the 1990ty years most. They were matured, flawless and had no environmental technology which harm the engine, require sensor technology and ECU's.
The company which from my point of view managed it best, to keep engines easy while fulfilling regulations is Mazda. With their Skyactive engine (compression+ignition petrol engine) they managed to match regulations without an EGR. But as it gets more and more tight, they will also hit the limits.
Other electronic stuff is simply required by law. I always get mad when I enter the Hilux and first of all I have to shut down all things which get me crazy before I can enjoy the ride. That's why I love it so much to drive with my Land Rover Series 2a....Get in, press the starter knob and go. A steering wheel, brakes, a speedo, a clutch and a gearbox, light and wipers. That's it.
