Putting text on the screen which would inform the user if the user was to read and comprehend it is not consent, no. (I mean, try to apply that logic to any other situation. You put a post-it note somewhere noticeable which says that you will silently mix some medication into your coworker's lunch unless they write some text on another post-it note placed on the kitchen fridge. When you then notice the absence of that second post-it note, and mix in some medication into their food, is that "consent"?)
Furthermore, looking at the asciinema from OctoSQL, users apparently have to edit their profile files on every single machine they intend to use Go on, then remember to verify that the profile applies and has no typos, make sure to never ever accidentally run the program in a context where environment variables aren't respected (would you remember to always use `sudo -E` if you need to use the tool as another user for example?). The danger seems extremely high that the user would, at some point, accidentally run the command without the env var set, even if they were technically proficient and did their best to opt out.
This is not how consent works.
Because that's how OP framed it. There is an ethical way to track how your app is used, with user consent.