They can be opened peer to peer, or hop between other channels, similar to dns routing
They are prefunded with a certain quantity of bitcoin that dictates the size of bitcoin that can move in that route at once - although smaller denominations can go through in rapid succession this just means more fees levied
All of this incentivizes a larger channel to be created by a well funded party, which can be coaxed into censoring transactions because they are a payment processor or institutional service. Likely an incumbent such as Visa joining the lightning network as a victim of LN’s own success.
There are some mitigations built in and actively developed. We are 8 years deep into Lightning.