The first time I've got my hands on a Z80 clone it was like "my precious". For example AY-3-8500 was not unheard of but was unobtainium in every respect.
If you're considering clones in East Europe, I think the real reason was economic. It was useless to have a complex circuit when the devices were not available. For this reason, most early clones of Sinclair Spectrum used only 7400 series circuits around Z80.
If you're considering clones in East Europe, I think the real reason was economic. It was useless to have a complex circuit when the devices were not available. For this reason, most early clones of Sinclair Spectrum used only 7400 series circuits around Z80.