These happen every single year. People firmly believe that every season has ruined League, changing their favorite aspects of the game because Riot's balance team doesn't know what they're doing.
The problem is that these perspectives are often flawed, and don't grasp the fundamentals of how the game functions each season.
For example, people say the game favors snowballing way too much, when in reality the game goes to 35+ minutes quite often. Snowballing has actually been hindered a lot due to catch-up XP, making champions like Lee Sin worse and tanks like Sejuani very strong.
People also say that the game is overly reliant on which champions are picked, giving the game a feeling of lower variety. I honestly don't understand these arguments at all, since changes to the pace of the game have made so many more champions viable than in previous seasons.
There are only 2 or 3 champions in each role that are truly bad, such as Shaco in the Jungle or Dr. Mundo in the Top lane. Even if tanks are strong, carry Top Laners like Riven are still playable and ganking Junglers like Lee Sin can still impact the game. No one showcases this better than Longzhu, who will give J4 to Khan despite what the meta dictates.
Finally, people believe that if there is not perfect balance in the game currently, it means that Riot doesn't know how to balance their game. First of all, people have the audacity to assume that they know far better than Riot despite probably never working on a game balance team in their life. Take a step back and realize that Riot has been doing this for years, and they most likely have a better understanding of how they want their game to function than 99% of people on these boards, including myself.
**If Riot hasn't changed something that you think is wrong, then the issue is either more complicated and challenging to fix than you comprehend, or they want this to be in the game and you need to adapt to it. It's still their game after all.**
In conclusion, the issue of Season 7 being the worst season yet is entirely subjective. However, if you truly think that it is the arrival of the 4 Horseman, you need to understand what's actually wrong with it. The biggest problems this season were Lethality at the beginning and Ardent Censor & Knight's Vow at the end.
Despite the game being focused on the ADC at this point, I'd still say this season brings welcomed champion versatility and intense matches where team-fights matter more than ever. This would've been my favorite season if Rengar hadn't have been changed, and I'm looking forward to the next season's changes. Also, Kayn is awesome.