u/DrAwesomeClaws

That is all.

Is there historic reason or anecdote about why they do that?

The more things change, the more they stay the same.

If you've ordered glasses from them, you can go to:

https://www.zennioptical.com/myAccount/myOrders

My page just spins. I was curious where my glasses order was after a couple weeks of not receiving them.

The network tab shows 30+ css files being downloaded for a very simple website, 10+ trackers and advertising js scripts, and the page still won't load.

How about this:

SELECT * FROM orders WHERE customer_id = :id ORDER BY order_date

Then you can render my most recent orders on the server and at least render some HTML with relevant data.

Ok, at scale that might now work. I understand that. Zenni isn't Amazon or Google, but they probably get many requests.

In that case we could set up 1+ load balancers that simply forward the request to a sharded server based on userid to balance the load. It's absolutely crazy that we could handle thousands of requests per second in the early 2000s with a few servers in a colo facility and these days everyone has to pretend they're facebook or myspace that needs to analyze complex graph connections between people. I just want to see what the status of my order is. It's not that hard.