I find a lot of names fall into this style because boy names historically experienced fewer and more gradual naming shifts.
I would consider some names ‘core’ traditional as they’ve remained perennially popular over the last century. I would put [name_u]Jack[/name_u], [name_m]Samuel[/name_m] and [name_m]Adam[/name_m] in this group. I would also include [name_u]John[/name_u], [name_u]David[/name_u], [name_m]Andrew[/name_m], [name_u]Joseph[/name_u], [name_u]George[/name_u], [name_m]Thomas[/name_m], [name_m]Calvin[/name_m], [name_m]Anthony[/name_m], [name_u]Charles[/name_u], [name_m]Victor[/name_m], [name_m]Alexander[/name_m], [name_u]Robert[/name_u], [name_u]Michael[/name_u], [name_u]Wesley[/name_u].
Others, like [name_m]Hugh[/name_m], have been used over long periods of time but have never been overly popular or saw a larger increase or decrease in usage at some point. These names often seem to be hiding in plain sight.
In this group I would include [name_m]Louis[/name_m], [name_u]Edward[/name_u], [name_u]Arthur[/name_u], [name_m]Christopher[/name_m], [name_m]Patrick[/name_m], [name_u]Walter[/name_u], [name_u]Francis[/name_u], [name_u]Gabriel[/name_u], [name_m]Simon[/name_m], [name_m]Peter[/name_m], [name_m]Dominic[/name_m], [name_u]Julian[/name_u], [name_m]Isaac[/name_m], [name_m]Joel[/name_m], [name_m]Malcolm[/name_m], [name_m]Richard[/name_m], [name_m]Alan[/name_m], [name_m]Stephen[/name_m], [name_m]Mark[/name_m], [name_m]Colin[/name_m], [name_m]Gregory[/name_m], [name_m]Martin[/name_m], [name_u]Timothy[/name_u], [name_u]Jesse[/name_u], [name_m]Matthew[/name_m], [name_m]Paul[/name_m], [name_m]Abel[/name_m], [name_m]Cyrus[/name_m], [name_m]Hector[/name_m], [name_m]Roland[/name_m], [name_m]Conrad[/name_m].