There has been a tendancy imo to overrate Cork's hurlers, particularly when it comes to their skill levels. But fwiw I think players can improve, and in some cases improve dramatically, with the right coaching and if they buy into it and are willing to challenge each other and demand higher standards. Lots of examples of this, Lohan with Clare being a recent one. Man for man, how many Clare players would you have thought three months ago would get into Limerick's starting team? Obviously a new management team won't automatically improve things, but it is honestly hard for me to see the current set-up making much progress, and in that situation it makes sense to look for alternatives.
When it comes to the current Cork panel, there are definitely specific things that can be improved, or at least where it's reasonable to think that improvement is possible. A few obvious ones - picking players in their best positions, working on tackling and holding opposition players up (especially among the forwards), hitting high-quality ball into the FF line (a lot of aimless looping ball was dropped in on Tim and Connolly last Saturday), even something as basic as switching on when the ball goes dead, especially on the opposition puck-outs (look at scores conceded to Clare and Galway where there was no-one within yards of the man receiving the ball).
Moving beyond the current panel, or at least beyond recent match-day 26s, there are questions as to which other players should be getting more game-time or being worked with on specific aspects of their play. To be clear - I'm not for a moment suggesting that there are many players in the county who *right now* would improve the first XV. I'm saying that beyond the changes I mentioned in the previous paragraph, there are areas where Cork need to be strengthened and where this might require looking at different options - one example would be playing at least one or two more physical forwards who are better able to win their own ball.