There are no electrolytics in phones, and most newer phones don’t even have tantalums. So long as there are no flexing stresses induced, which is nearly impossible with the way phones are constructed now, the all MLC capacitors construction has the potential to outlast any PC motherboard or laptop by a large margin.
The most critical issue is board connectors and moisture ingress. The USB-C connector or any other high pin density micro sized connector with a tiny pin pitch, and large electrical potential will fail from charge cycling and a resistance forming between pins. USB-C is particularly bad because reversing the connector doubles the number of pins on the board in a ridiculous amount of space. Just using a standard USB-C connector when ordering a prototype to be fabed at any common board house will double the price. The USB-C pin pitch is too tight for the most common fab process resolution.
The pin pitch only matters for high power application to prevent arcing, and that can also be resolved through the most modern USB-PD standard (See: USB-PD Extended Power Range, which can support up to 240w), and the electrical adjustment you have to make are all on the device side.
I don’t know about the resistance forming between the pins, for low cycle applications the cheapest gold flash plating would easily last 10K plug cycles, and accounting for corrosion from hand sweat/oil/hand lotion, many companies favor going for thicker hard gold or platinum plating nowadays. (Rhodium is the absolute best, but it’s just too expensive now to do at scale because they are used in catalytic converters for electric cars). USB-C lasts for many more cycles than the Micro-USB standards before it (You can read the 4 axis and wrenching test standards for mechanical testing on the USB spec) so I’m not sure what you are talking about here.
Lab tests rarely reflect the real world. I’ve seen several issues with Pixels that had an issue with PD failing due to moisture, corrosion, and a bridge developing at the connector.
Actually, no, the lab tests are standard with all products of all large companies, and they are usually conducted in extreme conditions, like 100% moisture at 80-90C oven for 48 hours and highly concentrated salt spray kind of extreme.
You bring up the example of Google Pixel, yeah, because it’s Google, they are software people who think they can just cheap out on hardware and save a couple of cents by making it up in software. Look at the Nexus 5X and 6P, both devices had an absurd amount of quality control issues compared to the other products made by the manufacturers, and the only factor in common between them is Google.
