I used to fly QF a lot in my younger days, and loved QF. That was because my company was paying my fare and I had access to Qantas Club and regularly get to fly J. Now, I don't fly as much and usually only max 3 times a year for personal holiday.
My last QF flight was MEL-PER using QF9/10 trying out the 787-9 J. I self-funded the flight at over 4K return, and I find that QF discriminate against those leisure pax with no status. When I booked my fare, I found only back 2 rolls of J cabin were available to reserve on QF9 and QF10. I was told that the good seats are reserved for QFF Pax. Onboard, I was all but ignored with just standard meal service. I had to physically go into the galley to find a crew to get a bottle of water. Or simply the call button on my seat was totally broken (but on both legs??).
When I flew with SQ J or F, I didn't have issues with reserving seats (e.g. 3A or 3F on 388, 11A/12A on 77W) and I got treated equally as other J/F passengers. I personally held no status with QF (just bronze) and SQ.
Lastly, when I call QF's call centre to make a change, I was met with hour-long wait then someone in a land far far away who can't speak English. While on SQ's call centre, my call was answered straight away by someone who can speak English (with Singapore accent) and followed up with a personal email communication to confirm everything is fixed/updated.
I have 3 trips coming up, SQ J trip to BKK in June, then SQ F trip to FRA in August, finished by a EK F to DUB in October. I really do find that talking to SQ and EK's staff in call centres to be far more enjoyable than QF. Plus on air, SQ is just consistent in their level of service. QF was too inconsistent for me and I felt discriminated against (maybe because I have no status or Asian looking).
Note: Never flown with EK before, I will be flying EK for the first time in my life. EK staff were extremely nice over phone and even though I do not qualify for Dubai Connect program they just gave that to me and followed with email on collecting the voucher at check-in.