Ask him to design us a currency for a homeostatic environment, because we're going to use it whether he likes it or not.

He's a Chemistry tutor. He clearly knows his shit.

He clearly has a personal bias, perhaps irrational. I feel no need to confront these kind of people with a positive version of that. Just sounds like an argument about religion that way.

Let him be

Depending on the specific location, this should be possible with relative ease, and relative low cost. Rebuilding a washing machine to accept bitcoin, can be done for under $50. The one factor where you have to look at, is what does internet cost. you can hook all washing machine to basically a single mobile connection, but preferably you're gonna want a hard line. Dependable on where you are... these might be expensive, but overall they are pretty cheap (you should be able to get one for a low as $10 a month)

One factor to also keep in mind, is that you gotta adjust with exchange rates, with the way prices going now... it won't be fun to all of a sudden having to pay 20 bucks for laundry...

I don't think the current block size is ready to handle the transactions for all washer/dryers in the world. Probably a better idea to use BTC to reload your laundromat card balance.

so... if we aimed all the Hashing power of the Bitcoin network on one address it would take 500 million years? Hey man It's only a matter of time before insane quantum computers just start cracking the codes by the second. I can imagine this will happen one day, when the Bitcoin network migrates to a new protocol based on quantum security. Those computers will tear Bitcoin apart when they finally are able to produce them in mass, and start migrating all the accounts to a new system like a block reward, Or just like the free market migrate by choice to something safer.

They can be destroyed by mining.

The protocol limits the miners reward to be less than or equal to the amount of the subsidy plus fees.  I am not sure if it was intentional (can't think of a reason) or simply an oversight but this means the reward to miner can be less than the subsidy and fees.

So miner creates a block with tx totaling x BTC in fees and y BTC in subsidy and gives himself 0 BTC coinbase reward.  x + y BTC have been permanently destroyed.

Likely due to a poorly designed miner in the blockchain there are a few blocks where the coinbase is less than subsidy + fees and thus coins have already been destroyed.