I've always felt that Oneplus is a brand that I should like on principle of having clean software with barebones but powerful hardware, but in reality, every single Oneplus phone I've seen always had some sort of big BUTs attached to them, so buying Oneplus always feels like settling.
Take the Oneplus One for example, that sandstone textured cover was THE most creative material I felt a phone could have had, and I'm honestly shocked nobody has ever done it again. But along with that of course, comes with the cringy "smash your phone" marketing campaign, the half-hearted attempt to distance themselves from their parent company Oppo, the whole software mess with CyanogenMod/OxygenOS, etc.
Had a Oneplus 3T for a while, same deal: Great phone when it works as intended, but they raised their price without making the phone better, and the inexplicable random restarts/battery drain is so irritating, never had another phone that does that.
Recently they've dropped all pretense of not being Oppo and abandoned their core audience, choosing to have the "courage" to drop the headphone jack. Mediocre Chinese phones with flagship specs are a dime a dozen, I just don't see a reason to buy them anymore.
OnePlus 6T: had it for 1.5 years and sold it because it had some weird bugs (can't remember exactly which).
OnePlus 8T: had it for almost 2 years. Updated to Android 12, was shit after few weeks. Factory reset to 11, used that a long time. Updated to 12 for a a few days and then to Android 13. Was alright but again a few bugs. Factory reset it again a few (staying on Android 13). Later Factory reset it to Android 11.
I have factory reset it 5 times in 1 the last year i had the OnePlus 8T.
And despite the many factory resets, every few days had a bug where it became so slow it wasn't useable anymore and had to reboot.
Short story: OnePlus had a lot of potential and I bought a OnePlus 6T for the price and the good software support they had in 2018. I feel a little betrayed because they became so worse over the few years I had my OnePlus phones.
I now have a Samsung S23 Ultra which has good software support and yes it has some bloat. But i don't have stupid bugs and the phone stays fast.