there's no justification for any tier 1 player being unable to play any sentinel character (all take 0 skill in terms of utility), and some controllers like brim and omen which take little to no skill. I will admit harbor, astra and viper will take some time getting used to but I don't think they're anywhere near as difficult to play in pro as initiators/duelists. initiators are really particular with utility timings and duelists require the most mechanical skill.