I don't think anyone is stopping anything, really. It's just functions doing work: If one thing get's easier and cheaper and safer and is building a track record, all at the same time and without signs of stopping or running into any obvious issues, we are increasingly less incentivized to think up alternatives. I don't think that's unreasonable. In the end, the issue is mostly a very, very small number of people in all of existence, who are capable of meaningfully developing new technologies (and always at the cost of not advancing something else, because they would all be capable of working on something else).

We have been good about increasing the number of capable people, so it will not be one or the other, but even so, right now, it's harder to imagine a world with an abundance of top engineers making new technologies actually possible, than it is to imagine new techologies.