I run a video agency, and we lived every tweet of this thread.
It's why our approval flow is now one link - no client account, no passwords, timestamped comments on the video itself.
The bar was never Sprout. The bar is a slide deck. More on beating it as I build.
I spent days reading Reddit threads from agency owners - hundreds of comments - to understand what they actually use for client content approvals.
Not Hootsuite. Not Sprout. Not anything from the multi-billion dollar category built exactly for this job.
The #1 answer isn't even a marketing tool. And it's 20 years old.
So Google Slides isn't winning because it's good at approvals. It's winning because it's free, the client already knows it, and it holds nobody hostage.
Free. Familiar. No lock-in. That's the real spec sheet for beating it - and almost nobody in the category is building against it.