Yeah, even if the website itself gets less traffic than the places you syndicate the content to, it's at least a stable home base that's there if those platforms fall apart. Are you posting something that corporations or celebrities don't like/want to see shared? Then posting it on your own site means that the buck stops with you, and they'll have to force you to take it down in court rather than relying on advertiser pressure/'encouraging' the platform to ignore fair use. Did you do something controversial that means platforms don't want to deal with you or individuals want to ruin your life? Having your own site means you can generally tell them to pound sand. And there's no worries regarding things like forced logins, forced ads, obnoxious cookie banners (especially if you don't need to collect personal info anyway), age verification restrictions, etc.

Plus there's just a level of control over the design and features that you can't get elsewhere. Want to make the site look completely unlike any other? It's 100% doable, as plenty of blogs posted here show very well. Want to add a new feature like polls or surveys or quizzes or interactive infographics or what not? You don't need a third party service or some premium account, you just add it yourself.

Running a website is like owning a home rather than renting one. You decide what furniture, what colours, what utilities and service providers, whether you want pets, etc.

And HN is kind of like the HOA of websites, giving you notices about color choice, pets, and under construction gifs.