This threat seems very, very likely at some point. The cost of an attack wouldn't actually be that much to pull off. Even a short term (i.e. much cheaper) attack could completely destabilize the faith people have in Bitcoin.
Are we just waiting for an attack to occur before actually doing anything?
An attacker that isn't motivated by money will eventually attempt an attack. This isn't an "if", it's a "when".
Some billionaire, inherited wealth rich kid could completely devastate Bitcoin for under $50 Million.
Some people love to wreck shit. Rich guys that love to wreck shit? It could get ugly.
Somebody console me. I want to be wrong. What am I overlooking?
I had semi similar view about this topic as you untill i dug deep into BTC problematics. Thing is, it's not that noone is doing nothing, it's that noone can not do nothing. There are few ideas floating around that could not prevent but make it more costly to execute 51% attack, but they are very complicated and could have very negative impact on BTC. Dealing with 51% attack when PoW is in question is really really really hard. If it was any easyer, it would already be done.
If you really want to "console" yourself, i urge you to read some BTC documentation. It's not as easy to attack bitcoin eather....easy in like: oh look ill just spend this 50mil$ and BTC is gone. Nope...cant happen "just like that".