At home my PCs have CIFS/SMB shared folders, it’s handy and simple to use. However I can’t find an Android app capable of browsing these shares.
There’s Android Samba client and CIFS Document provider on F-droid but both require to know the exact IP and path, you can not just browse the network like on a PC.
Extra vote for solid explorer, but the browsing that was mentioned I want to say is partially a server side thing. If the desktops can see them than others should be able to as well, but the server has to respond to those broadcast requests looking for shares.
For my time on mobile though, putting some sort of frontend over the files makes life a lot more pleasant. Sure you can play a video or open a picture through mount, but only from the right network, and sacrificing a lot of custom built functionality like a dedicated media player would offer over accessing the raw files. That’s more a my use case thing though, preffering to do the more heavy file management stuff from a full size computer than mobile.