There are lucks more in casinos whose principles are not very clear, but sports betting is more tactical.
It is true, luck is something that we should always have and want to be with us because it is what will make us win in any casino game, but in sports betting it is another thing, it is a thousand times better to make good strategies, very good analysis to win, wisdom is something that greatly influences sports betting, in casinos knowing strategies, tactics is good, but it does not guarantee winning, that is something we should not forget.
You are right, casino games doesn't require skills at all apart from the table and cards games like blackjack and poker, if someone is being deceived that they can use any strategy to win games like crash or plinko, they would just end up being bankrupt because these games are based on luck. Like you already said, sports betting require the bettor to have the knowledge of sports they want to bet on.