What is required is an "industry wide" seniority system. The only way that is going to happen when pilots can be trusted not to undercut each other.
How do we trust each other? By having a financial stake in the ownership of our own crewing company, increasing the incentive to remain knowing that career development will be on a 'fair' basis, rather that trading conditions for promotion.
Entry for new industry joiners is the easy part. Existing crew transitioning to any new arrangement is a much more complex problem, though not insoluble.
This could provide an answer to the "race to the bottom" mentality. Once a critical mass is obtained, pilots will be begging to join, reinforcing its strengths.
Much work to be done, a radical change perhaps, but worth thinking about.