However, how companies earn money changed. In the 80s and 90s computers were marketed at professionals working in offices. Software was sold shrink-wrapped on disks. It was very costly to change software later (send disks?), you better tested it really, really carefully. The promise was often to make experts more efficient at their tasks: Software was customizable, had macro recorders and had a familiar interface of buttons, menus and docking sub-windows. Computers were used with keyboards and (finally!) mouse: Two very efficient input devices. People (including me) are nostalgic for that time, and that makes memory very selective: We probably remember the best software created by large companies with great teams. We also remember software created for specifically for professionals working with computers, many HN readers will be that people. And, last but not least, there were a lot of terrible UIs too, that we gladly forgot and for every fondly remembered non-standard, fun UI (bryce?) there are sooooo many terrible ones.
A lot of what irks people can be explained with shifts in how software got made, for which audience and for which devices: Having many small teams working independently makes a coherent vision for a product more difficult (but has other advantages), user customization became less important since products were more targeted to non-experts and it also can mess with your automated testing; moving to the web as main way to deliver software meant that some types of interactions (drag and drop, using large amounts of data directly) were harder to create than others; on the web, advertisement and subscription models became popular, leading to very different ways to advertise software in contrast to the former "buy the bi-yearly upgrade in a big box" and the web was more OS independent so the old one-system, one UI-standard did not match anymore.
So, a lot of what "got worse" can be explained by changes in the ecosystem that software-creation and software-use happens in and by the position of people that assume it "got worse".
There are many things that I find worse now than in the 90s but this perspective can help to see if software got worse just for people similar to me and it can also help to find ways to make sustainable changes that fit the ecosystem that exists today.