I’ve thought some about this.
It is definitely most important to secure the protocol and harvesting and we do this with P2P nodes well. As for API nodes serving data to light clients, we are making it very easy for people to do so. Where as in Ethereum and Bitcoin it is very difficult for community members to run API’s for light clients, in Symbol it isn’t. Most people will earn money for running a P2P node, but if there is no extra drain on resources, many will choose to run an API node altruistically.
I’ll use myself as an example. I buy servers on AWS and like to prepay for three years in advance. But because I’m prepaying for 3 years, I also get slightly larger than needed specs. Now I have that extra hardware and bandwidth, I could chose to run only a P2P node, but why not run an API node too? I don’t have anything to lose and it helps the network.
So for me personally, running an API node in Symbol is a “why not, it will help the network and doesn’t cost me anything extra,” where as in Bitcoin/Ethereum it takes major service providers like Consynsus providing Infura for Ethereum, or Bitpay or Coinbase providing APIs for Bitcoin.
Also, as others have mentioned, anybody building a product on Symbol, will most likely want to also run their own API node just to make sure they have 100% uptime. Many of these will be available to the public too.
So at this point in time, I’m not so worried about there being a lack of API nodes on Symbol in the future. I think there are enough incentives in place for many people to run them. I can’t say this with 100% certainty. We will have to watch and reexamine later. But for now I think it is okay.