Thermal conductive glue. Is there any good?

What is the best thermally conductive adhesive? I mainly need it to stick the heatsink to sbc. I already ordered this tape, but I guess I would prefer glue. I usually used Fujik, but it dries for a very long time, even up to several hours. I need something that dries faster and has good thermal conductivity.

Additionally, why do adhesives have such a very low thermal conductivity compared to ordinary paste?

https://www.techingredients.com/product-page/thermal-epoxy

Apparently the best out there

And it sucks compared to thermal paste, so it is better to use thermal paste+separate mounting method.
Even if the mounting is done with some JBweld on the edges.