While this is absolutely true in my experience and Google Analytics has handled most of my needs in contrast with a homegrown data lake or ETL, there's always the spectre of Google pulling the rug out from under you with service shutdown or massive price increase.

Use off the shelf stuff but be prepared to have to move in a (relative) hurry.

"Google Analytics" is, as I understand the original context, shorthand for "something simple, cheap, and immediately useful." Feel free to substitute Mixpanel or some Show-HN-Google-Analytics-replacement Docker image or whatever.

Hook Microstrategy up to your lake then. If they just want inbound analytics and conversions then IT were probably recommending a data lake out of their own want to make it, rather than the actual need.

Who besides your hypothetical salesman is arguing that the raisin d’etre for data lakes is user web analytics?

In my experience people arguing for data lakes talk a lot about some unspecified future benefit. Companies typically want to learn things about their interactions with their customers that allow them to make more money, and thus GA or its equivalent represents the 80/20 — or more likely 80% of the benefit for 1% of the cost — solution.

Your statement implies a lot of assumptions about a business’s model. Our company cares about user interactions in our app, software development metrics, quality metrics, sales metrics, etc. GA is just one small piece of the puzzle.

“Data lake” may not be the right answer, but GA certainly isn’t.