I have gotten travel insurance during extended and more expensive trips and not for shorter trips. For example, TDA riding across Africa was expensive enough that cancellation insurance was helpful. On a shorter few week trip to Mexico or Thailand, I haven't bothered.

I've been fortunate to never have made a claim on insurance when I've had it.

As mentioned above, travel insurance often has several components:
- trip cancellation; I've seen this as a separate rider and if so would only get it if my trip was particularly expensive
- repatriation
- medical costs overseas; typically a lot lower than USA, so more interested in catastrophic events if possible
The cost of the insurance will also vary for countries you visit, e.g. expect coverage for visitors to USA to be a lot higher