Sony mostly pass the camera quality test†, the "fit and finish" test, and ship a relatively clean Android OS.

You also get options to have otherwise-long-forgotten features like 3.5mm headphone jacks and MicroSD slots, and Sony's waterproofing is second to none for phones that you wouldn't naturally describe as "ruggedised".

There are unavoidable issues around pricing (high) and availability (low), but by most of the metrics people would choose to measure phones' quality, features, performance, etc, they are actually doing a great job with their products (at least now that they also offer a respectable duration of OS updates and support).

If you are looking for it too, they tend to be at the upper end of manufacturers for open-source code and documentation availability: https://developerworld.wpp.developer.sony.com/open-source/aosp-on-xperia-open-devices, though with that said due to the relatively small audience for their products, availability of other people's custom ROMs will not necessarily be extensive.

I'm on my fourth of their phones (Z2 2014, XZ2 2017, 1ii 2020, 1vii 2025), every upgrade time I've looked around, and every time I've failed to find something I want to own more than another one.

† The caveat here is they're highly skewed toward operater control; you're very much expected to participate in the photo-taking process and I'm painfully aware that's not what most people want these days. Low assistance provided, basically zero "AI" processing, just lots of rope with which to hang yourself. It'll take beautiful pictures once you get accustomed to it though, whaddaya gonna do?