One year has passed since the Chaos Arena was destroyed, Asagi and Sakura were presently on an abandoned street on a man-made island that floated on top of Tokyo Bay. It was an enormous box-shaped island built by the government and referred to as “Tokyo Kingdom.”

Why is Modern Pokemon anime terrible?

Ratings. You see, back in the BW era, the Anime was losing its ratings.
So the folks over at OLM (the studio that makes the Anime) had a call to make. Option 1: Make Pokemon childish in order to appeal to the younger audience. Option 2: Make Pokemon a bit Mature in order to appeal to the bit older Audience. With the Pokemon XY series, they chose the latter and went with a bit mature theme. It didn't help the ratings. So now with the next and latest series, they decided to go for a childish feel with the Sun & Moon series. It worked. Pokemon S&M is now being targeted at its core Audience of 10 year olds.
And they like the show enough to not change the channel.
Ratings are steadily climbing back as well. What exactly happened? You see, during the XY series’ runtime in Japan, another series rose to challenge XY.
“Yo-Kai Watch".
This series has a childish feel to it, and drew all of the young japanese viewers from Pokemon to itself, resulting in poor ratings for XY. Also, there's the topic of Merchandise.
Younger 10 year olds are more likely to purchase Pokemon merchandise when compared to say, a 15 year old. So there you have it.
Pokemon isn't appealing to older people/Terrible because of Ratings & Merchandise sales. Do keep in mind that this is my personal opinion on the subject matter.
And there's also the huge debate over the Art style change in the Anime.
Ash looks weird, which is something I agree upon.