By that logic, we can say the same for everything else.
"Bow is reel ez, you just aim and shoot"
"Sword ez two! Just aim an clik"
"Fishing rod is reel easy aslo!!!? Just aim where u think he go an clik it"
Alright, flint and steel requires right clicking the ground to light people on fire. Switching to other weapons are irrelevant, flint and steel is the art of lighting players on fire or using it for defensive purposes.
Now flint and steel can be placed in a 4 block radius. So essentially 16 blocks to get a player on fire if they're charging at you. And most players are generally easy to predict at a close radius. This is what in my opinion makes flint and steel easy.
Now, you try and say with the same logic applied every other weapon is easy. However I disagree and believe that they require more skill.
A player who is 'good' at the sword should know how to perform each technique, strafing, crits, block hitting etc. These are all techniques which require precise timing. Flint and steel requires placing a block of fire down. Hey, half the time people just run into it even if it was placed a few seconds beforehand.
Bows are one of the most complex items in the game. Predicting a players movements is hard and that's why, IMO there are hardly any outstanding bow users compared to FnS users.
Fishing rods are actually fairly easy in my opinion to get the hang of, but perfecting it is also hard. Regardless of if you're using it for fishing rod stuns, knockback it requires very precise timing.
I'm not calling any FnS user bad, I just feel right clicking the ground in a small radius isn't as hard as other aspects to the game.