Your expectations don’t seem to match any other field of human endeavor I can think of. Nuclear plant safety doesn’t; rocket launches, no; pharmaceutical trials, nope. Perhaps we’ll be better and smarter in the future, but…I doubt it.
With regards to rocket launches, pharma, etc. those are all somewhat novel domains: experiments where risk is a natural part of being the first time trying a set of variables. The variables in air traffic have been the same for decades, thus the thresholds for accepted risk should be much lower.
If US nuclear plants haven't significantly endangered human lives since 1979, it's because the thresholds for accepted risk became so low as to render new enterprise impossible.
Regulating air traffic control (and thus air traffic) into impossibility isn't a realistic option. Unlike nuclear energy, which has functionally equivalent alternatives, there is no functional equivalent to the speed, reach, and cost of air travel. We likely already hit the practical floor on incidents in ATC a long time ago, thanks to (as you have observed) the variables involved being very stable for decades.
Hence the cause for alarm: what if, all of a sudden, those reliable variables are changing?
Couple that with capitalism (the 737 max's design, oversimplified, resulted in two disasters due to a for-profit company trying to maximize profit and minimize time to market by hacking an existing platform to compete with a new and ostensibly better one) and it's a surprise we're doing well with air travel at all.
That air travel is as good as it is is a great case for techno optimism. In spite of all the garbage we get ourselves into, we manage to make it work.