No, but you can just take one off the shelf and adjust colors / fonts.
- How do you manage product consistency without it?
You'll need experienced designer that knows how to gradually build it. Otherwise I can't see a way without.
- Do frontend engineers complain about not having one?
No, because we have one, but they complain when components could be used but something slightly different was designed.
A friend runs a consultancy and we recently spoke about it. They build e-commerce type of websites, they start with a simple mockup, once they are ready they build style guide/components. All other pages are just assembled from these components - don't think this works for completely bespoke software, but it demonstrates that in some cases it's integral to the rest of the process.