I feel like every single manhua I read has a non-canon sex scene in an extra/seasonal bonus. I’m not complaining I just think its funny
That's how you get readers who will sub and pay for extra content. At least, that's the Webtoon model.
After binging most of the manhua on this site recently, I'm thinking the pacing in these is just a feature of the ultra loosey goosey publishing environment. We're talking creators with less exposure to and more removal from a massive professional publishing institution, like Japanese indie/doujinshi creators, and creators (I assume*) less exposed to a history and practice of formal indie/doujinshi creation, like webtoons creators. Which is to say, less exposed to western expectations of narrative creation. It all feels like work done without editors, but many of the authors mention having editors, so that's my hot take.
*China, it turns out, produces more doujinshi overall than Japan and has a convention that surpasses attendance of comiket, but this is a relatively new feature