I think there are different aspects to it.

Amazon’s delivery service is better than ever. You get products in half the time, with less packaging, and fewer miles traveled to deliver it to you, without any significant increase in delivery fees.

Price is still competitive when you take into account delivery cost and speed. If you don’t care about those, Amazon isn’t the cheapest.

Search and reviews are down the tubes. It’s like Amazon no longer cares if their site is overrun with crap products as long as people are buying them.

Amazon still works great if you only buy name-brand products that are fulfilled by Amazon.