Avoiding innovation is not simplicity at all atleast from my perspective. Every era has it’s own needs. If smartphones were available that time, I believe our beloved Prophet (SAW) might have used it to convey his message to larger populace.
Everything is concerned with use. It depends on us how we use it.
Islam is not just offering prayer and reciting Quran. It is to delve the hidden treasures concealed in Quran and the world but our religious scholars will not emphasise us to do so even.
Initially when train was introduced in subcontinent some renowned scholars called it dajjal as well.
But yes there are many other things which must be brought under consideration while using it . It is also a fact that smartphones are mostly controlled by a place which is considered hostile to Muslims. May be for that reason they prohibit its use