Existence of Ulrich bundles on polarized surfaces and weakly Ulrich bundles on polarized varieties in positive characteristic

In their seminal paper \cite{eisenbud2003resultants}, Eisenbud and Schreyer asked whether every smooth projective variety admits an Ulrich bundle with respect to each very ample polarization. This question has stimulated extensive research for more than two decades. Recently, Anghel \cite{anghel2026