They have been viable since the end of season 1, always dominating anyone who dare stepped foot in the support/adc role bottom lane. Aside from the morde days (and even then, you just ban one champion and you still have 100% adc/support bot) adcs will always be in meta. It will never be like assasins or bruisers or tanks who are dormant for a year then are able to be in meta. Not since season 1.
Right now as it stands marksman ( besides the obvious quinn graves n jayce who are not marksman ) are struggling.
Unless you're playing Vayne you will find yourself hating each game.
Constant 4-5 man bot lanes and the sunfire ninja tabi poppy who makes you auto her for 39 damage..
Arguably the problem is less Marksmen as a class and more the Farmer Lane position. The amount of pressure on bottom lane is massive and it is forcing champs to back much earlier than usual or risk dying. You're averaging 800ish gold on a back unless things go massively in your favor, which means that gold i just going to sit around uselessly while you wait for your BF sword.
Take a look at the Marksmen doing the best right now. Most of them rush items that allow them to buy a Longsword or two on their first back. That means they can do useful things with their gold despite the massive early pressure being dropped on the lane. Being able to snag two Longswords instead of being forced to sit on your gold until you have enough for a BF Sword is a huge advantage right now.
