I heard it's bc the most popular novel site only shows the title so they started packing the entire description onto the title to try and get attention, which led to this mess
Thats mostly to do with more and more manga being adapted form lightnovels and then that style of titling starting to affect manga original titles as well. Although as soon as you filter out the generic Isekai garbage you'll find most mangas have decent names.
I have enjoyed the training diary, but I'm seriously addicted and have tons I'm reading. So the actual quality is both suspect because of how much I read between each chapter and how low my bar for reading is.
It did feel like the recent arc of taming this one monster was a little dragged out, and then I was a little disappointed by the actual result of it.
It's been like that for a while. "No Matter How I Look at It, It's You Guys' Fault I'm Not Popular!" (aka Watamote) has been going since 2013, and I guarantee there's earlier examples.