I bought my house on a contract that was based off the national standard contract for residence transactions. Deviations from the standard were clearly marked. Regardless the contract was read to me by the realtor when I signed for the intent to buy, and the most important points were reiterated by the notary when confirming the actual transaction. It was great I found it useful and comforting to know I was signing for, doubly so knowing it was mostly the standard contract everyone else signs for.
That said. Your "10s of millions of wasted person hours" is a twisted way of presenting the data. Reading the contract was 30 minutes. That's 0.00019% of the time I will spend paying my largest monthly expense towards.
House sales are complex enough that most people use common template contracts, simply because it makes the interaction with the required third parties (realtors, notaries, public record offices, lawyers, banks) more efficient by a large enough margin.
Rental however? Almost everyone uses their own crap contracts or some decades old template contract, and usually there is no one involved except the landlord and the renter. And because there is no need for more efficiency, the market can't and won't push for standard contracts.
I love Nova Scotia’s standard rental terms, with generous term for tenants:
> Use these forms to show the terms that must be part of any lease signed in Nova Scotia. The lease a landlord uses may look different, but must contain all the items shown here. If any of the items are not part of the lease a tenant signs, they apply anyway.
Either 2/3 or 3/3 of the apartments I've rented since graduating college have used a similar template to one another, where part of it comes down to checking boxes or filling in a blank space. They each had some variety of addendums, but shared a common core structure.
This was also at apartment complexes that had multiple units, so maybe it's different if you're renting from an individual for a one-off space.
That said. Your "10s of millions of wasted person hours" is a twisted way of presenting the data. Reading the contract was 30 minutes. That's 0.00019% of the time I will spend paying my largest monthly expense towards.