in my opinion the key is in "who can run a lightning node/hub?" as long as it is anybody who wants (which is the case and now there is incentive to run a node) then i don't see any kind of centralization in this.
what's the incentive? how much can you expect to make in fees? i guess it matters how well-connected your node is. you have to weigh that incentive against the risk of keeping your private keys online too.
for years people have been running bitcoin nodes but some of them have been complaining that there should be an incentive for it. the fees can be that incentive they were looking for. they may not be a lot but it is still viable. the thing is people have never been getting paid before and they were running nodes but now they have that perk.
You do have a point there, mate. Anyone could leave or join a Lightning node at will, in a decentralized fashion. However, there's a thing that might concern LN node operators which involves regulation. I've seen an article over the web which says that Lightning node operators could be classified as Money Transmitters which fits on FINCEN's regulatory presence.
maybe true. but first they have to consider bitcoin itself as money so that those who are processing its transactions to be "money transmitters". and so far only a handful of countries have considered bitcoin as money. for example US considers bitcoin as commodity so how can they consider its transactions as monetary?