For reddit at least, The money from VCs dried up. They have to monetise fast or go broke.
Elon way way way overplayed for Twitter and the company is hemorrhaging money paying the loans he took out to pay for the purchase.
Google in general is in decline. Ad sales are down as the net becomes SEO’d to death. Marketing teams just aren’t willing to pay for Google ads like they used to since the roi isn’t there anymore.