Best approach for managing core block CSS? (Experiencing FOUC when dequeuing unused styles)

Hey everyone,

I've been working on optimizing a few sites lately by moving away from heavy page builders and relying more on native blocks to keep the footprint light.

One issue I keep running into is managing the overall size of the core block CSS. I'm trying to conditionally dequeue wp-block-library and only load the specific styles needed for the blocks that are actually rendered on a given page.

However, I'm occasionally getting a frustrating Flash of Unstyled Content (FOUC) on the initial load, especially on mobile and when caching is enabled. I've experimented with inline styles for above-the-fold content, but it feels like it's becoming a bit of a maintenance headache.

Has anyone found a solid, reliable workflow for this? Are there any specific hooks or techniques you prefer for conditionally loading native block assets without breaking the initial render?

Would appreciate any insights or hearing how others are handling this.