The frameworks have NOT gotten slower! God I hate Hackernews sometimes... whats really going on is actually that not a single dev reads the release notes / improvements / learns how to actually use the framework. If anything, the latest React release was almost purely a performance improvement release (and has been for a while) ...most people need to fully understand a tool they use before complaining about it.
Everyone always wants a frontend framework that "just works" - sounds a lot like a free lunch to me! You have to manage the state and updates of your application at some point - the underlying software cant just "guess" what you want. But I'm always like a broken record when these react hate / <insert frontend framework here> hate threads show up - most of the confusion is derived from lack of basic concepts of what problems these frameworks solve in the first place.