there is a happy balance but it is also personal preference
some people are just happier with clean surfaces and plenty of empty space and everything apart in cupboards or drawers and like the so called minimalist aesthetic of either monchrome or naturals white and wood.
Other people like having less stuff but like colour so although they do not have much stuff it is their favourite colours so it is minimalist but not minimalist aesthetic
other people like the colours of the minimalist aesthetic but just want more stuff they do not want a capsule wardrobe or only 3 pieces of decor
others like the electic style of all pieces that mean something to them without going with any particular aesthetic
what works for one doesn't for another
as long as the space is useable, and safe it is fine, and you can find stuff when you need it. However if you live with other people you need to bear in mind their preferences you can't impose on them, if they like spaced out clothes in their side of the wardrobe you can't fill these spaces with your stuff, on the other hand you can't go throwing other peoples stuff away without consent unless it's a hazard like mouldy food or something with sharp edges that could cause injury or blocking stairs or windows
The problem with living with hoarders is they often fail to respect boundaries and start filling your space with their stuff or creating safety hazards or causing financial hardship by buying more stuff with money that should be used for other things or they create so much stuff that the rest of the household is too embarrassed to have guests over
it is OK to have stuff for a hobby then outgrow hobby and declutter it, it gave pleasure at the time so it wasn't a waste of money but keeping it may no longer make sense
many people buy things for a fantasy self maybe they think of themselves as an outdoorsy hiking person and have back packs hiking gear several walking boots but the reality is that they don't hike they do country strolls and it lies unused. or maybe you have lots of going out outfits when the reality is you just wear jeans and nice top and you have 7 unworn wedding outfits that you will never wear again it is OK to change hobbies if you liked card making or playing the piano once but not any more that is fine it is not a failure to stop doing one thing