First of all, I’d like to make a distinction between monarchists and royalists. Monarchists is a political group with certain believes around the structure of the government. Royalists on the other hand is a cultural group that enjoys certain events.
If you look at the cultural artifacts of royalists you’ll find they enjoy and attend events around, for example royal weddings, they gather in forums where they share gossip around, e.g. the Romanovs. It doesn’t matter if they like to keep Putin as president, or if they would like to re-inaugurate the Romanovs as tsars, as political believes are orthogonal to the culture (although I do admit it would be kind of weird to find an anarchist royalist). To that extent I think of royalists more like Eurovision fans.
Likewise if you look at the quintessential prison abolitionist Angela Davis. Now describe her speech, her hairstyle, her public events, etc. You’ll find many prison abolitionists that don’t share any of it, however if you’ll look for people that share these cultural artifacts, you’ll find a bunch of radicals. Radicals is exactly the cultural group which I would ascribe Angela Davis as belonging to.