Yea but thats not really an excuse, is it? They offer a service, (some) people pay for that service and should therefore expect it to work. If GitHub cannot keep up with the growth then they could disable new account registrations or start reducing free tiers so people either use the free tier more mindfully or need to pay for usage-base products like Actions which would GitHub allow to scale.

Not a valid excuse without knowing what their historical growth rate has been. And how much of the instability is load related.