I always thought fender-benders were a rounding error, especially for large insurance companies. It's the catastrophic accidents, involving deaths that cost a lot of money.
Of course higher repair costs due to general inflation, newer cars having lots of sensors etc. add to it as well, but the agents I talked to specifically cited general comprehensive (not collision or liability) claim concerns as one of the main reasons.
It's common to have coverage will be reported as single injury/multiple injury/property in thousands. Six months coverage, paid up front.
For state minimum 25/50/10, I've got a quote of $117.
The max separate limit quote is 250/500/100 for $158.
They also quoted a combined single limit (which I think can be used for any mix of injury and property damage?) from 100k for $134 to 500k for $165.
This is just for liability. Uninsured/underinsured coverage is extra (I'd recommend it, but leaving it out for ease of comparison). Comprehensive and collision is extra (and I wouldn't get it on a 20 year old vehicle unless it's a collector's car, but that probably needs specialty insurance).
From this quote (which may not be accurate or representative, more data welcome), it seems like paying about 50% more, takes the coverage from about $60k to about $500k of liability. It doesn't make a lot of sense IMHO to not consider taking the max coverage. If you want more, umbrella policies are available and also not usually very expensive until somewhere around $5-10M of coverage, depending on your insurer.