I only note one sentence: When the network is congested, your transaction in the mempool is just waiting in line—if your bid isn't enough, it gets bumped or even prioritized by miners/validators to be processed first. In the end, you either have to increase your fee and resend or just wait and pay the failure fee for nothing. So don't just look at Layer 2 trash talk about who has higher TPS and lower fees; when the network is crowded, how the mechanism "arranges" you is the real key.