All science is materialistic

[LinuxGal]

The essence of science is the scientific method: to test all ideas via observation, to only consider ideas that are testable (usually falsifiable) and to agree to modify or eliminate those ideas that are shown wrong via observation.

Nothing in this method *requires* 'matter' or even 'physical' aspects to be fundamental.

A particle is fundamental when it is determined to have no constituents.

An electron, for example, is fundamental, while a proton, made of (fundamental) quarks and gluons, is composite, even though energetically a proton has no decay channel (under the Standard Model at least, if not under assorted proposed extensions to the SM).

Fundamental implies that the chain of inquiry has terminated.  The masses of fundamental particles (if they have masses) are simply brute empirical facts.  This makes for an unwieldy theory, but it's the best we have.