I currently use Logbook of the World and eQSL to electronically confirm my contacts. I wish the ARRL would accept both for DXCC, but they don’t, so LotW and physical QSL cards are the only way to get the League sponsored awards.
However I will gladly mail a physical QSL to anyone who sends me one. No SASE is required (and in fact will simply be returned unused with my QSL).
Here is a copy of the front of my QSL