I'll take that one, whilst I'm here.
It's a bit disingenuous to keep hearing this line from other fans. The support has steadily grown since we got back into the Championship. The City has been starved of any notable success for decades, it's not happened overnight.
2021–22 19,541 12th (Championship)
2022–23 19,950 5th (Championship)
2023–24 25,468 9th (Championship)
2024–25 29,177 5th (Championship)
2025–26 30,000+ ??st (Championship)
Just as success brings in the fans, failure loses them. Hence why your attendances dropped to 20k in League 1 and then rose a bit to low/mid 20s in the following 5 seasons back in the Championship. Your fan base is no different to ours in that respect.