Most open source software licenses explicitly say there is no support.

> ... the commercial license can be their existing OSS license plus an invoice

Of course, Patio11 was running his own show, and a larger company might demand more, but it is worth asking.

Support contract:

1. For the given amount of $5000 for the period 2023-01-01 to 2023-12-31 you are entitled to

2. Create a feature or bug request on our support system

3. Have a first response back in 96h

4. No warranties explicit or implicit that we'll be able to solve your problem blah blah blah etc

And then you are on vacation and some asshole in legal sues you because you didn't respond in time when a dev had a small problem they could've solved by looking in the source code for 5 minutes but wanted support instead.

Way too risky.

Agreed, this is only an example (but as you grow you can have someone look at your email - this is part of why it's a good idea to offer support contracts)