Because VC money has dried up. For a very long time tech companies have had investors throw them basically infinite amounts of money and have proceeded under the idea “we’ll figure out profitability later”, now that money is starting to stop coming in and they are panicking and trying to reach profitability in the shortest amount of time possible.
That’s not what’s going to happen. I really don’t understand why people on Lemmy are so fussed about this, Meta are not building a lemmy instance, they are building a twitter clone. While yes you can access Threads content through Lemmy that doesn’t mean it’s going to affect the Lemmy ecosystem. Mastodon is going to be way more affected than Lemmy ever will be.
Just because they are on the Fediverse doesn’t mean it will make sense to use their services through all other Fediverse platforms and vice versa. Following an entire Lemmy “sub” on threads will be a shitty experience and Threads doesn’t have creation of subs as an option, the only viable equivalent features are user posts.