First, with the tier 2 system, the process for employers of obtaining a sponsor licence is difficult. It does not receive intense scrutiny by the Home Office. There is no right of challenge to the Home Office decision, and therefore many employers who wish to run a tier 2 scheme to sponsor migrants, although they are bona fide employers, get cases refused and are not able to challenge. The starting point of the scheme is unworkable. The insistence on pedantic documentary requirements, which many employers cannot understand, leads to a lot of cases being refused, so the system is not workable at present.
With regard to your second point, yes, I think there should be simply a declaratory system for EU settled status. If the British Government wish to require EU citizens to justify and document every day of their existence in the United Kingdom when at the time they did not know they would have to do it, it will lead to a load of perverse and unfair outcomes.