The page itself states, "(Tor nodes excluded)". So that page is only displaying information about less than 30% of the total number of nodes on the network (source).
So this statement:
More than 30% of all LN nodes on the mainnet running on 5 cloud providers is a problem.
Is incorrect. It would actually be 30% of 30% are on 5 cloud providers, which is 9%, as far any anyone can actually prove.
And private channels
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