Actually, I think there are still some real room for improvements for any TWS on the market (almost 90% are missing a CD quality lossless codec).
I bought these last 10 years many types of TWS and kept them almost all (B&O, Apple, Sony, Cambridge Audio, Samsung, Victor, ..). Actually I think the HA-FW1000T is the most convincing TWS I own concerning sound quality (Buds2 pro and 1000XM4 are not really far).
But the HA-FW1000T are still a real step behind my 2 favourites IEM HA-FW1800/XBA-N3 plugged with a balanced cable to my BTR7/UP4(22)/GoBlu (BT receivers with LDAC mode).
The HA-FW1000T with some little PEQ adjustments is a very good sound experience with an efficient Noise Cancellation, but user interface is just hopeless !!! it's a real pain just to change the volume level, and it's very slow to react for any changes (pass-through, next/back tracks,...) ... but, I prefer it over the Samsung Buds2 Pro even with the seamless codec activated.
I have some hope with the future 1000XM5 from Sony, to allow a real lossless CD Quality transmission like any of my LDAC BT receivers with some improvement concerning sound quality (maybe less dull ?).
On my side, I feel more comfortable/confident to buy and use "industrial" TWS with important research centres, strong quality controls & measurements like from Sony, JVC, Apple, Samsung, ... than almost any individual integrator/company which are making fully hand made/3D printed which, maybe, would have difficulties to produce some consistent "sound qualities" at a reasonable price. I would think a firm like FIIO is an "in between" company, and can manage to produce at reasonable price some really consistent audio devices with good service.
NB: Actually, a Sony NW-WM1A (In BT LDAC receiver mode) + XBA-N3 or IE900 + Z Fold4 is my sound quality reference as portable & streaming audio system.