I think some people have a different and too high expectation that make them feel disappointed by Ragnick approach and the progress being made.
We're not an established top 4 team that can achieve necessary result to secure top 4, while going through style modernization mid season. Finishing 3rd and 2nd under Ole proved nothing. I doubt established top 4 is a thing the past few seasons, seeing how Poch's Tottenham crashing down so fast despite previous seasons consistent top 4 finish. And last season Klopp's Liverpool barely wrap up top 4 finish despite arguably the top team the previous 2 seasons.
This season was a write off seeing how slow the people at the club act to sack Ole. Choosing an interim manager in Ragnick instead of going for Conte or whoever else as the permanent also signaled that the result. Ragnick is leaving the manager role after this season, so to go extremist we can say anything beside relegation is within acceptance threshold.
IMO I rate Ragnick level around Brendan Rodger which is a decent coach with good ideas, and decent style, but with better vision and know how to build the club. In more ideal situation, Ragnick can get the team in higher place, but ultimately I don't see Ragnick have the ability to win against the elite coaches. If we have that more ideal situation, we want a better coach.
Right now, we're so behind from the like of Liverpool and Man City in style building. Even Tuchel Chelsea with a head start, and more collected approach to football from executive level is showing gap of the progress. It's unrealistic for us to get a helicopter improvement from the directionless messy football style we just came out of.
What we need from Ragnick is setting the first building block for our style, and starting to create that more ideal environment for the next coach. Klopp and Pep were trophyless in their first full season. With Pep had the benefit of his friends doing some basic building block prior to his arrival. The squad Brendan Rodgers left is nothing great to crave about, but there is element of fundamental in style that help shorten the learning curve for players when Klopp took over. Ragnick doesn't have that benefit. He's almost building up from ground zero in term of coaching.
Without preseason, long term fitness, stamina build up regime, new signing, there is a limit to what we can progress within this season too. Now getting some fundamental of his style imprinted into the team, and priming some future key players of this squad is what I personally expect. Low standard? Maybe. I fully accept this season as a write off. I am content (not truly happy) with the progress this far. The style has some sense in its despite still full of hole, error, selection (management) issues (I disagree with).