You're not describing a sybil attack. You're talking about censorship.
If you want to address that, your best strategy is to incentivize people to run access points that do not censor. This requires payouts to routing nodes in proportion to the value of the transactions they process, which requires the ability to make routing payouts, which requires a sybil-proof routing mechanism.
If you want to address that, your best strategy is to incentivize people to run access points that do not censor. This requires payouts to routing nodes in proportion to the value of the transactions they process, which requires the ability to make routing payouts, which requires a sybil-proof routing mechanism.