What's the consensus on "Solo Leveling" and "Demon Slayer"?

Background info (not necessary to read): I am VERY new to anime, in fact i was one of those guys who thought its not for me. I watched Cyberpunk Edgerunners like 2 years ago and i didn't really click with it.

But a month ago, i randomly joined the Discord voicechat while my friends were watching the first Solo Leveling episode and i kinda got hooked. We watched all Episodes and then we started Attack on Titan... Well, we managed to watch 3 Season in a week lol. Not that its that important, but i a newbie to anime.

Back to the question: Ive seen some controversy about Solo Leveling and Demon Slayer (i havent seen DS, but my friends want to watch it with me) and many people on reddit are saying that those two animes are animation only - no substance/lazy/bad writing. So is that just a vocal minority or is that the truth? I kinda noticed that with Solo Leveling, but it was still kinda fun to watch. What do you think?