That nuclear waste is being sent to countries having such facilities ; they also have some recycling capacity\expertise. Also introducing blockers where you don’t need them seems a bad idea for me always. This is currently very hard in Germany since almost every transport of Castor containers which are filled with high level nuclear waste, namely spent fuel is accompanied by substantial protest. This is why the nuclear waste is stored in intermediate sotrage facilities on the surface in close proximity to the actual waste producers.

Also transporting nuclear waste has it’s own risks. For example one such transport derailed in France: “On February 4, 1997, a train carrying spent fuel from the Emsland nuclear power plant derailed in the French border town of Apach .” Luckily there was no nuclear spillage, but I still find this extremely unsettling. Hard to imagine what happens when something like the Eschede train disaster happens with a nuclear transport. Also the Castor containers currently in use had originally a lifetime of 40 years. A substantial amount of these containers will reach this age soon. So it was decided to prolonge this life time because of political considerations. There is currently ongoing research if the Castors are able to hold the spent fuels safely until a long term storage facility is available in Germany, the earliest date for which is suppoed to be in the 2050s.

Sources:

https://de.wikipedia.org/wiki/Atommülltransporte_in_Deutschland (Google Translate: https://de-m-wikipedia-org.translate.goog/wiki/Atommülltransporte_in_Deutschland?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp)

https://www.deutschlandfunk.de/atommuell-zwischenlager-sicherheit-castor-100.html (Google translate: https://www-deutschlandfunk-de.translate.goog/atommuell-zwischenlager-sicherheit-castor-100.html?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp)

https://en.wikipedia.org/wiki/Eschede_train_disaster