SHARES was crap at CO. I flew with CO before 3/3 and had the same problems that we are facing now: zero upgrades, no TOD offers, random seat reassignments.
IT was fine when they operated as Texas Air and people express with limited connecting opportunities and no worldwide network of partners. Drop it in with the "big boys" and its an utter failure.
wrt OP's question. CO management is running the combined airline like they ran CO. With complete disdain for their "over-entitled" customers and full of an undeserved arrogance. United was running pretty well before CO, and then they threw a wrench in the works because they knew better. CO flyers either had no choice or were used to being treated like dirt. The results speak for themselves. By FAR the lowest ontime percent in the industry, by FAR the most complaints, by FAR the worst financial performance the last few months.