There are several ways to attempt to measure fragility. This BAML graph illustrates the recent divergence.
I don't personally do a generic measurement of risk. For me, it's how often do I lose x dollars in a day on non-positional trades or how often am I subject to sudden non-reverting price dislocations. Since I primarily am a market maker, large non-reverting dislocations with no increase of volatility to follow through is the worst type of environment. These are certainly becoming more frequent.
Not to say that there isn't plenty of compensatory good stuff going on in some markets but most MM firms are fairly specialized to 1-2 product spaces.
Also. Nobody wants to sell equity index vol at these levels. The only people who are doing it are forced to because that's their main business.
The best thing a retail trader can do with options is to buy individual equity names. Those get mispriced because the MMs can't practically keep on top of all the nuances of every individual stock so they take shortcuts.
