As you say, the team is talented enough to compete with most teams in the league. I think that Petke's coaching has been beneficial in some ways: making players compete for time, getting more young guys on the field, etc.
However, it also seems that in his 2+ seasons, we have had more lopsided losses than in previous years combined (5-1 at home against LAFC, 4-0 at NYC, 4-1 at Philadelphia just last season come to mind). Also under Petke, we have had some head-scratchingly bad losses too (that 4-2 loss to a bad Minnesota in 2017 or the 3-1 loss to Orlando City last season when they finished 22nd).
I'm not necessarily on the Fire Petke bandwagon, but something isn't right to have all of these really bad losses. Maybe it is the tactics and the counter-attacking style that he wants to play and maybe it has something to do with his quotes about trying to chase the game and getting a result or pressing for an equalizer when RSL is already down a goal or two that is leading to these big margins, but it's hard to watch a team get worked repeatedly. And some of his game-day decisions are mind blowing to me. Justin Glad was solid all year and then sits the final games of the regular season and playoffs? Not playing Dani Acosta ever even when the team had injury/depth issues?