How is this not the same? I'm not seeing why you can't compare Halo with Counter-Strike. In Fortnite there actually are even mobile (iPad) players that put thousands of hours into the game and are better than 99% of PC players.
PC players that put thousands of hours in to a game are better than 99.9% of PC players.
But... both technically and culturally it's not the same as a PC shooter. Similar to comparing HALO with a game like Counter Strike I guess - one summer I was bored and shot 2500-3000ish heads (Aim Botz) in one sitting but I can't imagine "practicing" PUBG mobile in a similar way.