People use the term as if it's interchangeable. But it's not.

The titles are of course different
Founder – founded the company
CEO – runs the company

If it's the same person with both the titles, it is supremely critical to know the distinction

And I was made to realize it again day before

Founder – executes.
He knows what it takes to build the company, has a view on the market and the product.
Thus, a review meeting turns into a workshop
Where he identifies a problem and rolls up his sleeve to solve it

CEO – delegates.
He knows he has the team to build the company, bases his views on what his trusted people tell him, has his ears to the ground but knows that he cannot be the one fixing things
Thus, a review meeting remains a review meeting
This should be looked at again.
This is great
What drive this conclusion?
Yeah, we all agree this doesn't work. Fix it!
When he identifies a problem, he trusts his team to find out how to solve it
And he ensures there is nothing in their way, to do so

The important thing then is to know when to act as a founder and when to act as a CEO

During a founder conversation, don't become a CEO
During a CEO conversation, don't become a founder