This is in fact a watermark to promote the application, which otherwise wouldn't be recognizable since Bluesky looks like every other microblogging app. I didn't know that Sam literally named the file GrowthHack.tsx, which is pretty funny.
I can't help but respect the dev's self-awareness
> which otherwise wouldn't be recognizable since Bluesky looks like every other microblogging app.
The text at the top of the screenshot is
> Eric Roston
> @eroston.bsky.social
So it's pretty easy to tell IMHO.