These BIPs are definitely improves privacy for light nodes, but if user's unencrypted transaction goes through third party full node then I think there is still an issue with privacy.
Transactions are never encrypted but yes, Electrum does have some privacy concerns. If you do want to protect your privacy, you'll probably be looking at Wasabi Wallet, Samourai Wallet etc. Their built in privacy functions
I think you missed my 1 CPU 1 Vote argument. In the older days, mining requires a full node due to the pools being practically non-existent then and the profitability of a CPU was fairly decent. People are compelled to run a full node to mine because SPV wallets aren't really suitable for mining. Proliferation of ASICs and pools has also resulted in miners joining pools to have less earning varience as well as a higher reliability; they don't have to run full nodes to mine anymore.
Ideally, as many nodes as possible is the main goal. I haven't really found many businesses actually running their own full node. It's way easier to have a ready-made integration than to have to build the backend to handle transactions yourself. I'm not talking about those who are primarily dealing with Bitcoin transactions, but those merchants who see Bitcoin as an alternative form of payment and are likely not concerned about the disproportionate cost-benefit that having a full node would bring.