Even if you find way to pay full node which are very difficult to abuse and without locking big amount of Bitcoin, it won't solve block size controversy.
Without changing total bitcoin supply, each node only get very small amount of Bitcoin (which already mentioned above) and it won't cover cost of running full node.
Yes, the fixed mining reward distorts the incentivization too much to properly investigate appropriate rewards for running a full node. But the same problem applies to transaction fees. It is crucial to solve both issues before the mining reward approaches zero.
I get the point, but it's more realistic to,
1. Increase block size as long as cheap/barebone PC (e.g. Raspberry Pi 4GB with 3.5" HDD) can run full node
2. Encourage people to use newer on-chain feature (SegWit, Taproot, etc.), batch transaction (at cost of privacy), LN or other side-chain/off-chain network.
1 CPU 1 Vote is about mining, not about full nodes.
And it's not even practical due to ASIC and farm mining.
IMO, disk space and internet bandwidth is scarce for the average joe. When alternatives like Electrum and other SPV wallets exists with little to no synchronization needed, most would choose them over a full node.
When alternatives that are better than running a full node exists, the average user won't run a full node. The tangible benefits is just too little.
I agree that for average Joe Electrum can be good enough, but there are still a lot of cases when full node is needed for businesses and even for regular users.
Regular user? If you mean privacy benefit, BIP 157 & 158 are enough for most users. Example wallet which uses it is Wasabi Wallet.