Find out who is posting NSFW posts and unollow them.

If someone is boosting NSFW posts you can always turn off boosts for that person.

Otherwise you will see the blurred post unless there is a browser extension or something that can hide them.

Voyager has a “Hide all NSFW” option

it's not an elegant solution.... but block the offenders

Provided they don't post NSFW, make your home page only show the communities you're subscribed to? Sorry if I misunderstood your question, but that's what I do and I can't remember seeing that much NSFW, if any.

Can you filter keywords to block very specific things you don't want to see? If a post matches those words you can make it so that post won't show up at all.

Issue is of false triggers, you won't be able to see what got missed. Examples: mastodon would filter out someone's post about someone being a dick to the cashier at the grocery store if the keyword is 'dick', and plenty of false triggers for 'fuck'. So filter out words like 'penis' and 'sex' instead.

the default android apps lets you block tags. I had problems with Irrelevent NSFW being tagged with some tags I follow, but blocking #boobs fixes most tbh.

I guess you could make a feature request in the mastodon project page. Or, on mobile, try a different app, each app implements a different set of features.

Depending on how the html is structured, you might be able to use adblock or tamper monkey to filter it out (in a browser. Apps are less supportive of this)

There is no such thing as NSFW on mastodon. The clients will usually hide the content behind the subject text to make sure the user reads it, if that's what you're referring to.