That's a really good point.

I haven't done a lot of optimistic updates with LiveView yet. I'm not sure how sanely you could really achieve it (because it seems you'd lose the primary benefit: server-side rendering / source of truth).

However, there are a few mechanisms you can use to note that the page is loading / processing a LV event that can assist the user in understanding the latency. e.g., at the very least, make a button spindicate. I've experienced (in my own apps) the "huh is the app dead?" factor with latency, which suggests I need to simulate latency more. If the socket is unstable or cannot connect, the app is just entirely dead, though the fallback to longpolling is satisfactory.

I think it would really shine for internal apps due to the sheer velocity and simplicity of developing and deploying it.

In the worst case, you could fall back to using regular controllers or APIs controllers, so I still see it being a "better version of Ruby" overall. However, if we're going back to this, I would rather use SolidStart and do it all in TypeScript anyway.

At the end of the day, I'm very torn between the resilience/ease/speed of Elixir and the much better type system in TS. The ability to just async something and know it will work is kind of crazy for improving performance of apps (check out assign_async)

> the majority of results are 300ms+

Another thing to consider is that a lot of apps (SPA powered by API) take 300~1000ms to even give you a JSON response these days. So if you can get by with making a button spin while you await the liveview response (or are content with topbar.js) I think you can get roughly close to the same experience.

> deployed 'at the edge'

The nice part of Elixir is you could probably make a global cluster quite easily. I've never done it though. You could have app nodes close to users. I think you'd have to think of a way to accelerate your DB connection however (which probably lives in 1 zone).