I did get a chance to read your original post this morning and had been pondering for most of the day about what to write - I needn't have worried!
There's no getting around the fact that the image quality from the GFX sensors is spectacular. It's not just in terms of resolution and pure sharpness but also dynamic range, tonality and the super smooth fall off. The quality of transition from focus to out of focus areas is superb even at slower apertures like f5.6.
All that said, I still love my X-T5 and if I had to plump for one system it would be my x-mount gear without a doubt. Furthermore, the price for entry to the GFX system (even for used) is getting a little silly now. A quick browse on MPB and WEX seem to suggest that a 50s II will cost around £2k and a 100s £3k. I couldn't even find a 50r for sale and I'm guessing those will get even rarer now with the hype surrounding the 100RF.
My first GFX purchase was the 50s II and 35-70 kit in May of last year and that whole package cost £2100 from WEX (it was an open box return). That is now an easy £2600 IF you can find both camera and lens in a good enough deal.
I actually only had the 50s II for a month or two when I spied a 100s on MPB for £1600 which just seemed too good a deal to pass up at the time. Admittedly it was a well used unit but as with most purchases from them it was in fine condition. Fast forward a year and you'd be lucky to find that same camera for under twice the price.
Personally, I don't think the costs of GFX are worth it right now. I can only assume I lucked out while the GFX was at rock bottom because it has only increased ever since. I said not long ago that I could sell all my GFX gear now and make a tidy profit despite over a years' use.
Long term it's difficult to say, but right now I don't envisage me staying with GFX beyond the life of
the [my] 100s. The X-mount system is still my preferred choice and the options for it are improving all the time. The new Sigma is a case in point - I actually sold my GF 45-100mm in anticipation of that Sigma lens as they would both effectively serve the same purpose (for me) and the Sigma is a heck of a lot smaller and lighter.