Technology products come to mind immediately. Products are becoming more and more deeply integrated with less serviceability. Phones are obvious, but more insidious are things like soldered on storage and ram in computers, the inability to replace failed storage in game consoles, known defective designs not being addressed, or taking a long time to be addressed (joycon drift, butterfly switches).

There's also software related things, like not being able to get the software or firmware to program a replacement part, even if you have access to it. Putting modules in parts that don't require them, just to flag them as "unauthorized repairs" (ask a farmer about John Deere) that are all put in place to use the digital millennium copyright act to circumvent the magnuson moss warranty act.

Even little things, like integrating the controllers for HVAC and lighting relays into the radio of a car, so that replacing it is more difficult or impossible stand out.

You also end up with fashion companies in the mix too, wanting these same laws to cover knock-offs of their products.

You also see this in the latest wave of appliances as well. A lot of proprietary parts, that do the same job as a generic part that has been standard in machines from the 60's to the mid 2000's. The lifespan of a refrigerator has shortened drastically as well.

I wouldn't say it's a conspiracy, so much as a mass market move. A device that has a long lifespan and is serviceable isn't profitable like a new machine, so make the machines less durable. As old machines are phased out for machines that are drastically better in efficiency and other metrics, those new machines won't last as long.