We haven't seen what actual game progression will look like within the expansion, but I feel like if progression ends up looking similar to vanilla with the vast majority of resources going towards science production, the quality mechanic will not even be a large part of the game if science itself has no benefits from increased quality, so I hope that there's more news to come on how quality will impact progression. It feels like this information about this was intentionally left out in today's update, likely to allow diving in deeper in future updates.

I think most "casual" progression around building more "factory parts" in vanilla usually looks like a single assembler slowly churning out items to fill up a single chest (or a few slots within a single chest), and just letting that run while focusing on other active tasks. I think quality will help make that specific part of progression a little more interesting, with needing to recycle lower-quality products back into the manufacturing chain, and/or tiering your outputs and prioritizing putting the best machines in certain areas while saving the mid-tier ones for other use cases. The randomness factor is concerning on the surface, but at least based on the numbers presented, it looks like the ability to produce items of a specific quality is very much intended to be a consistent factor, and not something akin to like hunting for rare drops in an RPG that tend to be tedious.

"Nerfing" Speed Modules by cutting their quality seems a bit reactive to the traditional/overused "assembler w/ Prod3 modules surrounded by beacons with Speed3 modules" setup, and I'm not sure if this is intended to shake that up so that there isn't a single "right answer" for every type of product being manufactured, but given that current Factorio is what a factory with all "worst" quality manufacturing would look like, this feels more like unlocking new ways to grow the factory that aren't just scaling out the same patterns from before, so I think this might be okay.

Overall I'm pretty excited about this within the context of the expansion. I think this is a good way of producing a different and fresh new experience to building the factory, while not invalidating the way Factorio has worked before, and I expect that future FFFs will be showing more about progression within the expansion and other new mechanics that play off of quality to provide similarly different experiences from the base game.