In reply to Steven Gliebe.

I don't think I can ever be OK with a plugin putting a credit link in the post content, particularly if there is no way for the user to remove it without writing code. That is the user's space, not a place for plugin authors to advertise. It's not a place to gain exposure, regardless of the price of the plugin.

Can you imagine what the modern web would look like if every block or shortcode plugin done this?

A theme or plugin simply putting a credit link in the footer is an entirely different situation. When I was on the theme review team, I know the team suspended at least one theme for intentionally making it hard to remove the footer credit link and upselling paid removal. Not sure how the team feels about it today.