> The juniors only get to run the show and introduce exotic, non-boring technology (asynchronicity, event-sourcing, eventual consistency, CQRS etc.)

That’s decade old technologies. So is most of the functional niceties which are somehow finally hype nowadays by the way.

The idea that junior are somehow better able is as old as the field and every junior ends up seeing the light at some point.

It generally goes like this: junior thinks they are smart and have a good solution for an apparently new complex problem. They build it and it fails because of some unexpected edge case. They reluctantly go to see the senior expert with the problem who immediately understands the issue, tells them not to do what they just did - they tried this apparently good idea ten years ago - and proceed to give them a solution which will work. Junior dev finally realises that senior are just people who have been there long enough to already have done the obvious mistakes and they can gain considerable time by just learning from them.

Obviously it only works if your senior are actually senior and not slightly older junior with ego boosting title.