With the absurd amount of Assassin and Basically-No-Cooldown fighter types, reworks, and new champions now in the game, champions like Syndra, Ziggs, Veigar, Lissandra, Viktor, etc. have become extremely weak, barely seen, and even if you can manage a win - you feel exhausted doing it.
They have been weak for quite a while now, with several problems about mages and their counterparts never addressed...
* They're inherently late-gamey, most of their time is controlling creeps waves and battlefields and zone-of-controls than raw dogging their enemies under turrets and using a built in low cooldown teleport or dash out to not get punished.
* Their combos are too weak, hitting someone with your combo-starting stun or lockup and then letting loose your abilities deals next to no damage early and costs near all of your mana, as opposed to the likes of a two-shuriken zed, Akali, or Qiyana now - only after you have 2-3 full items will your damage feel useful and games end so quick now thats not easily done at all, in addition to the fact Assassins and continue to mow down entire teams if fed where mages are still limited by their cooldown times, usually eliminating one opponent at a time unless they can AoE, then having to recharge.
* Extremely long cooldowns for the above abilities. With most assassins, their cooldowns are innately very very low - you feel like you have to dodge their combo enabling abilities or massively overtuned damage every 4 seconds or die and succeed for minutes, all the while desperately trying to find an opening for your 18 second-CD stun - and then die because they flashed instead.
* The majority do not have an escape tool, and pushing in your mid lane is extremely risky and has the most number of jungler access points. Most assassins won't worry, they need only Fizz E, or LeBlanc dash and can weave clear just as well now since Riot feels assassins should be able to have access to AoE damage spells instead of accepting that champion archetype should have weaknesses.
* The only saving grace they have is hourglass, however due to the very short cooldowns on the above assassin abilities, this is not likely to save your life unless a teammate is their to ward them off, ironically hourglass is ten times better for the AP assassins mashing your face in than you. Other mage items cost way too much and do way too little for control mages.
* While most of the issues I rant are of assassins, even the new juggernaut-style champions such as the like of the new Mordekaiser, Warwick, and more all are constantly being rework to either have dash or gap-closer/pull tool to "keep up" with the meta that is leaving mages high and dry - as well as insane tankiness allowing them to ignore most control mage poke with shields or heals.
* Lack of creativity, mages don't get reworked, and its been so long since we have had a new Control mage that is actually unique, Swain was a good one, but drown out by the new Pykes, Qiyanas, Neekos, Sylas, Zoes. They all seem edgy and new and cool but its really just Champion can dash (usually more than once), Champion can stun, root, silence, taunt, charm, sleep (pick any three), and then kill you - overloaded kits and overtuned damage every time. The game has been paced by all these new additions, without any signs of slowing down.
_Rest in peace true Mages, may you one day be able to lane again... at least maybe you might end up as a support if you get lucky with quick-fix bandaid buffs to your damage. And Anivia, keep going strong, you are the last of them. _