Nope, not a client problem. It depends on how you connect to the services, through which network & how many relays allow your requests to go through etc. If it works well for you, you maybe don't have a lot of different connections & the servers are more available to you. I don't know.

Or I mean, you could define this as a "client problem", but if you do that, then nothing will ever get fixed, because every client configuration will be a "client problem" as in "not my problem" and the actual issue will persist. Not every "client problem" is not "not your problem".