Where are you located?
SOUTH EAST ASIA
This will have an impact, that is for sure, because the latency will be longer. For example. The latency from my location to the data center is around 30ms. From your location around 180ms. CDN will reduce that. The question is: Is the latency to root cause or not? The only option to test it is to measure it.
You said you are using the CDN, but I don’t see it.
PROFESSIONAL EDITION (Does it not switch on CDN with Squidex automatically for assets API Calls)
The CDN is described here: https://docs.squidex.io/02-documentation/developer-guides/api-overview#cloud-cdn-beta
In general a CDN is not free, it cannot guarantee fresh data, therefore you have to opt in to use it.
Currently Only CMS - Squidex is backend (Server will come in next few product iterations)
I have seen that you are writing an angular app and you are making a few calls from the angular app to squidex CMS. They are very fast on my machine, but the initial page load is very slow. Therefore my assumption is that you are making a few calls in your backend as well. Are you doing server side rendering? If yes: Can you disable it for testing or can you cache it? If not: Why is it that slow?