But something like n8n I would consider using, because you've provided an escape hatch to lock-in by making the source available. I think it's totally reasonable to prevent other companies from profiting from your work. I also think it falls under the umbrella of "open source". If someone wants a truly FLOSS version of this, they're welcome to make it themselves. But they won't, they'll just complain and keep using n8n, because the licensing is good enough for 99.9% of use cases.
EDIT: I just want to point out that there's been some discussion of licensing here which I've personally found interesting and instructive. I've seen several people suggest that there is a definition of the term "open source" that is essentially universally agreed upon (that being the Open Source Initiative definition [0]), and that that is the only valid definition. I've worked in what I consider to be open source for many years, and wasn't aware that such consensus had been reached. My personal views have not changed as of yet, but my paradigm has definitely shifted. I intend to pay closer attention to how others use this term, and carefully attempt to be clear about my usage in the future. Having a single agree-upon definition of things is always valuable, and if that's where we're at I'm all for it. I'm just not convinced yet that it's actually 100% agreed upon.
That said, I think the author of n8n was pretty dang clear.