The reason this situation is implausible is because the time it would take to get to a $1million per btc price tag would allow for significant technological developments, making mining more efficient as well as energy infrastructure, energy generation etc.
This misunderstands the argument. It doesn't matter how cheap electricity gets. If every day there are one billion USD worth of bitcoins distributed to miners, then miners will spend almost one billion dollars per day trying to get these bitcoins. This is standard economic theory, and you can see why this is true via a proof by contradiction. If miners were spending significantly less than 1 billion USD per day, then any miner that started spending more money on mining would make a profit.
There is simply no point in conjecturing around something which is so far into the future that you cannot even begin to comprehend how different even the most basic functions of life will be.
We have very good reasons to believe that Bitcoin will NOT somehow overturn the most foundational truths of economics. This argument is so general that it doesn't depend on the exact particulars of the future.
Bitcoiners why you ignoring the fee?
The fee is irrelevant to the argument I'm making.