So after researching of some technologies I got possibility to create "Level 2 modernization".

But I have no clue what exactly triggered the possibility. In this topic https://www.games2gether.com/endless-space-2/forum/65-general/thread/21473-system-development-upgrade-bug-with-sophons I read about "Neural Robotics" but I still not researched it despite I have "Level 2 modernization".

What are prerequisites for all levels of system development? This thing is very unclear in game.

Found the tooltips in next era requirements

Unlocking new era in "Economy and trade" gives you next level of system development.