Icann introduced caps on tasting/deletions long ago, registrars are allowed no more than 10% of their total volume and there is a non-refundable fee. So tasting is no longer free.
That is for .com etc
Certain TLDs terms have more liberal terms.
Dynadot may be a good place to taste, within certain limits and if you don't mind the non-refundable fee.
Godaddy may also grant free deletions on case by case basis, but it's a courtesy.