Thunderbolt 5-equipped PCs have just started shipping and there are already a few vendors with compatible 80Gb/s SSD enclosures:
Acasis TB501/TB501 Pro enclosure
LaCie Rugged Pro5 (2TB or 4TB)
OWC Envoy Ultra (2TB or 4TB)
SSI SI-9229TB5 dual M.2 (for Mac mini)
SSI SI-8220TB5 dual M.2 (for PC)
Trebleet TRE-8132 enclosure
Wero TBT5002 enclosure (JHL9480 + JMS583)
Winstars WS-UTE50 / Wavlink WL-UTE50 enclosure
Wintop WT5 enclosure