There are waaaay too many abandoned assets on the asset store.
They waste time and money for us consumers that buy them.
As a buyer you can get a clue by reading through reviews and comments, but that means that someone else had to buy the asset and essentially waste their money.
I don't begrudge asset publishers for what they provide - developing and maintaining a product requires a lot of effort, however the worst offenders leave old broken garbage which they can still charge money for - and the effort is on the consumer to request a refund afterwards, perhaps forgoing the purchase of a better alternative.
The best developers are actively updating assets with bug fixes and new features every few weeks or months.
I suggest assets that are not maintained be demonetised, which will help buyers see that using the asset is a risk, and it will also give publishers incentive to regularly update and maintain their product.
So maybe after 6 months / 2 unity sub-version iterations without any updates, the asset price is automatically discounted by 50% and is clearly labelled as being behind in updates, rather than on sale.
After 12 months / 4 unity sub-versions the asset is automatically discounted to free ($0), or a negligible cost that does not benefit the publisher, and is labelled as un-maintained.
The asset will return to it's monetised state if it is updated.
Of course there are some assets that stand the test of time, however the updates do not have to be major, a minor update could qualify, it just proves that the publisher is actually looking after their product - even if the changes are not required.