dx was basically a dropshipper, so sometimes it could take a week for your item to be gathered up. Then it was usually 2-3 weeks from China for me in Canada. de minimis threshold didn't matter so much when they declared everything as "toy - $5".

I'm surprised they got the dx.com domain name: must have cost them quite a penny. All dead now.

Dunno about Shein and Temu, but I think Aliexpress at least charges sales tax for US purchases nowadays.