I agree Roman Abramovich and Todd Boehly are similar in how quickly they want to see results but they handle player transfers and team decisions differently. Abramovich trusted managers to choose players they wanted and provided money to get them. He also let scouting team find talent. Boehly on the other hand signs players he likes even if manager does not want them. And you are right this can cause problems like we saw when Mauricio Pochettino said he did not know about some signings. And I also think if Boehly keeps making decisions without listening to manager Chelsea might struggle again this season.
Both of the have more similar to get quickly process for winning trophies, but under Roman Abramovich era give full controlling to manager sign players they want, difference under Todd Boehly lack trusted the manager sign any players they want and recently some recruitment based on instruction from Todd Boehly not considering from manager instruction. Its main reason why Pocehttino reach mutual agreement contract with Chelsea indeed he has several years contract left but don't get more space for signing players he want and management make to much instruction recruit new player.
However, Roman Abramovich is the best Chelsea owner right now comparison with Todd Boehly have been second season but get much failure and Chelsea never finish on the top fourth standings position including bad habit sack manager every season.