You can have a 100Gb uplink on a dedicated fibre for less than 1000$/month now. Which is insanely less than cloud bandwidth. Of course there are tons of other costs, but that alone can suffice to justify moving out of the cloud for bandwidth intensive app.
Just curious where do you get 100Gb with Internet transit and dedicated fiber for 1000$/month? I'm in a small town in eastern Germany and looked for a simple Gigabit fiber access for our office without any bandwidth guarantees and it's 1000€/month for 1Gb here with the most budget provider but with some nebulous bandwidth guarantees. I'm not talking about residential fiber that also very expensive after a certain threshold. I know there is init7 in Switzerland but it's the exception to the rule in Europe it seems. Getting a fast fiber and good transit is still expensive?
I'm in Switzerland, so maybe I am biased, I have 10Gbit/s dedicated on a 100Gbit/s link for about 600$/month. In practice I have 25Gbit/s with most datacenters in europe, 100Gbit/s with some that are close (OVH, Hetzner), and 10Gbit/s with the rest of the world.