It's not just about the signaling, it's about very practical realities that come to light when you need to use that equity. If I were an investor and I saw 33% of shares with a former co-founder I'd walk immediately. If I were an investor that saw 33% of shares with a former co-founder and then 25% gone in an initial $500k raise I would run, not walk.

There's just not enough equity left to incentivize, create an options pool, hire, raise future rounds, etc. It is a Huge red flag, and the likelihood of success decreases dramatically.

I tried to raise once with 28% of the company being gone from our seed round, and it was a major, major concern. If this company ever needed to raise again, they'd be dead in the water. Therefore, the founder ends up with 33% of nothing instead of, say, 5-10% of something, and it's in his or her own best interest to take a smaller piece.

Now 5%? Maybe 10%? That stings, but at least it leaves the company something to work with.