This is a thing I'd love to see data for - the strike price discount at time of acquisition for later-stage companies. These same companies in that megaround companies probably have stock on secondary markets, which might be a good proxy for some of this.

And totally agree wrt creative arguments being viable... Just not clear what ends up happening in practice. Ex: I can imagine a split between paper unicorns vs ones w revenue backing it up being closer to market, and those later ones often switching to RSUs. So genuine curiosity here.