Nope, not at all concerned. For one, the Nintendo branded case I bought came with a screen protector so it's totally fine now.
But even in the week or so that I went without any screen protection, I had zero issues with the dock scratching the screen, and I wasn't even all that careful putting it in. Like you said, I think it's a lot of paranoia.
Also, Binding of Isaac Afterbirth+ went on sale yesterday and that was an immediate buy to have that portable. There's a lot of gross-out 'humor' (I mean the main weapons for you and opponents are tears, urine, and blood... with lots of poop around for good measure) and religious themes, so I can't blame anyone who refuses to play the game based on that... but it's such a great game. Between the Flash original and the remake that uses a better engine, I'm up to 73 hours in BoI on PC (and I'm on the low end for people who play that game), but I have a feeling I'll surpass that pretty quickly on Switch just since I can play it while other things are going on on TV.
Speaking of playtime, after 10 days the Switch profile page switches from "First played on..." to an estimate of how many hours you've played. I've only bothered with one of the four main story things (making it super general just in case) and have been wandering, exploring, going to shrines... and I'm at "55 hours or more" played so far.
And I'll admit while I knew the ability to play handheld while around the house would appeal to me, it's making it harder to want to play via Xbox or PC (except VR). I admittedly barely use my Xbox One these days (except for EA games that I'd have to purchase via Origin on PC), but even Mass Effect or a lot of the PC games I would generally be playing, sometimes it's like I really wish I could play this laying in bed or whatever. I was super-excited about Mass Effect Andromeda, but haven't even started the free ten hour trial I get via EA Access because of that.
On an unrelated note, while Switch has BoTW, now Binding of Isaac, and will be getting Stardew Valley over the summer to round out the number of addictive time-sucking games... I fear for humanity if they put Civilization 6 on this thing.
Also, they did patch Bomberman and greatly improve the controls. And another thing... Nintendo really needs to implement a shortcut to change controller grip order or whatever. If the two JoyCons are connected as one controller, but someone takes the left one and wants to switch to two separate controllers, there's no way the left JoyCon can go to the 'change grip' menu. I feel like pressing and holding the minus or plus from the system menu screen should jump immediately to the that screen.