I'm reminded of an occasion a few years ago back affecting the Tyrone county ladies football team - for a few years the county team had been performing poorly in the Ulster & All-Ireland senior championships and a decision was taken to voluntarily regrade to intermediate at adult inter-county level. A few long standing county players objected to having the team drop a level and never returned to the panel, what remained along with a few fresh faces then fought on, reaching the IFC final after a couple of seasons and then winning it (beating current SFC champions Meath) to gain promotion back to Senior level. Alas, senior level didn't last long as they were defeated in a relegation final last year and will play in intermediate again this year. To me, that's the level Tyrone are at in the sport at this present time and that's where they (arguably) deserve to be, there's more to be gained at playing at the level you're competitive in & seek to earn the right to play at a higher grade rather than making up the numbers at a level where you're regularly shipping big defeats and going through the motions.
Now I know that the format of the Tailteann Cup doesn't mimic that of the female equivalent but I suspect that at some point down the line it will be, with the competition absorbed/renamed the All-Ireland Intermediate Football Championship - I see that the All-Ireland Junior Football Championship has been reformatted whereby no second string teams from Ireland now compete in it, instead there is a qualifying competition between "county" teams in Britain with two of them going forward to the competition semi-finals with New York & Kilkenny getting byes into that stage, and I'd not be surprised if in due course the intercounty football championship goes into a three-tier system with promotion/relegation between them.
In the short term, what would help gain player interest in the Tailteann Cup IMO would be for the winners of the competition to be guaranteed to be able to play in the All-Ireland Senior Football Championship not just for the following season, but the season also after that (so a two season minimum) regardless of National League or provincial championship performance. So for example if Down win the 2022 Tailteann Cup, then they would be guaranteed a place in the 2023 All-Ireland SFC qualifying stages even if they fail to get promoted back to Division 2 at the end of the 2023 NFL & fail to reach the Ulster SFC final - and it would also apply for 2024 as well, however if they were to play NFL3 or NFL4 for 2026 after the 2025 league and also failed to reach the 2025 Ulster final, then back into the Tailteann Cup for 2025 they would go.