If the instructions for the OSW beacons tell you to make the beacon uncopyable, then PLEASE DO SO!
Yes, it's an inconvenient extra step.
Yes, it's more convenient to leave it as-is.
Yes, you may pride yourself in enabling your visitors to copy every last thing from your sim.
Yes, it does work as desired even if it can be copied...
...until someone actually copies the beacon and then puts it on their own sim, not even knowing what it is. And as they don't know what it is, and as the beacon did not come with instructions (they copied the bare beacon and not the box with the beacon and the instructions), they leave it as-is. They do NOT change or remove the beacon key. Why should they? Nothing tells them to do that.
All of a sudden, the entry for your own precious sim here on OSW will switch between your actual sim and that other sim run by the person who took your beacon with your beacon key and dropped it on their own sim. And half the time, the people who want to visit your sim will instead land on that other sim.
Now you may wonder if there are OpenSim users who don't know that the website OpenSimWorld exists. Yes, there are such people. It's mostly newbies, but there seem to be enough people who start building sims of their own while still counting as newbies. And I dare say there are enough seasoned OpenSim users who still don't know that OpenSimWorld exists.
And those who don't know that OpenSimWorld exists don't know either what this beacon is and what it's good for. Actually, just a few weeks ago, I had to explain to someone who has been in OpenSim for much much longer than myself what the beacon is and what it does.
I myself didn't know right away what the OSW beacon is and does when I started last year. For me, the OSW beacon was nothing more than a nifty Hypergrid teleporter that some sim owners were kind enough to install on their sims. In fact, apart from catching the occasional landmark, the OSW beacon was the only way for me to travel the Hypergrid.
I did NOT know about the website behind the beacon. Nor did I know that the primary task for the beacon is to connect in-world locations to the website.
Had I started to build my own sim about a month into my OpenSim usership, and had I found an OSW beacon that I could (and still shouldn't be able to) copy, I would have taken it and put it on my own sim as it was, someone else's beacon key in it and all. I wouldn't even have known that beacon keys exist.
To cut a long story short: If you let people copy your beacon, people WILL copy your beacon. With no instructions. They WILL NOT know what it really is. They WILL NOT know there's also a box with it inside plus instructions, much less where to get it. And they WILL misuse the beacon. And the entry for your sim here on OpenSimWorld WILL malfunction.
And if you ABSOLUTELY HAVE TO make the beacon available to everyone, then at least put the original box next to it. Not somewhere else on the sim, but right next to the actual beacon so that every last dummy will find it. And if you think the box looks terrible where the beacon is, then put the beacon itself somewhere where the box would look better.