As someone who uses Sony Xperia 1 VI, yes can confirm it's absolutely amazing. Took me less than half a minute to unlock bootloader and root if you don't count the time for the mandatory wipe when bootloader is unlocked (per Android design), and you literally don't lose any OS feature other than Sony's proprietary video enhancement feature (due to DRM key voiding and DRM level demotion with unlocked bootloader), but it's pretty shitty anyway and only useable with the standard display mode, and if you're using an Xperia phone you're probably a photography/cinema/art enthusiast who would much prefer keeping the phone in the color accurate "professional" display mode anyway. And this phone comes with a very clean AOSP-like ROM with minimal customization from Sony (but those they did make are very good QoL features), so most of the Android ROM modding tools designed for Pixel phones would at least have most of the features working on the Xperia phone too, and you dont really need to worry too much about too much unexpected behaviors from OEM customizations with ROM modding, especially compares to the like of Xiaomi phones lol

But I'm not sure we genuinely have a feature with Sony smartphones. On the newer generation Sony Xperia 1 VII, Sony for the first time outsourced their flagship phones (the Xperia 1 series) to a 3rd party manufacturer instead of making them in factories which Sony owns and have direct control themselves, they have been doing this with their mid-range and budget phones before but this was the first time they did it with their flagship phones, and immediately there have been serious quality control issues resulting to many Xperia 1 VII phones failing prematurely and required motherboard replacement (according to some users who ran into issue early), and Sony later had to launch a whole recall for many of these phones: https://m.gsmarena.com/sony_announces_xperia_1_vii_replacement_program-amp-68647.php

Issues this serious and this widespread is pretty much unheard of for Sony Xperia flagship models, they may not had the most advanced features or sensible pricing, but they have always been known to have at least some of the best build quality, except longevity issues on the Samsung-made OLED screens on gen V model which was more of a Samsung's fault and it also affected Samsung's own phones using the same OLED screens anyway.

And all this is after they already stopped officially selling smartphones in the US and China markets with the 2024 gen VI model, which are arguably two of the biggest smartphone markets, and with the 2025 gen VII model Sony announced they are significantly downsizing their operation in the EU.

At this rate, there might now be a new Sony Xperia phone in the next 3-5 years.

Asus is good too

Edit: not any more