That's the stupid way to look at stuff.
No, it is not like modern games are stupid, not at all.
The question is, whether you really need to waste the skill and slot to get it, or whether you would like to have it as full dedicated character.
The question is how you choose to balance your build out, what are you willing to sacrifice.
Now most people will generally agree that combat skills do make difference, so it's pretty nice to have a choice here.
But this FA/Doctor thing is a bit weird. If you wanna be a medic, there is no way you are taking just one, for everyone else, you will mostly have both undeveloped anyway.
First aid and doctor can't be undeveloped, if you can't max it out, it doesn't mean it has to be or is useless. What this suggestion is suggesting can be achieved by just lowering CD for both skills, so that they are more effective with less skill points invested. Merging is just what the truck, it is the same thing, if you merge both skills in the end you will need to invest twice as less skill points to be effective by having access to both of the mechanics that normally are two separate skills, witch if they stay in that way just purely leaves the player with more choice how to optimize and balance his build. Merging will allow more tag skills somewhere else, but at a cost of a skill what previously was something completely different than "medicine skill."
For science and repair it's similar, currently the purpose of those things is rather to reach a cap to allow you doing things, rather than enjoy being scientist or technician.
Yes you could search for some better use for science. But the results will not vary from the basic reach-the-cap scenario. If you have dungeons when you need science to open the door, it's just annoyance with specific character requirement. If you want to add full computer mini-game, you are basically moving further from fallout than by merging the skill with repair.
Science and repair is nothing similar, being a mechanic or a scientist, apples and oranges and no you don't need to cap either of them to use them in game somewhat effectively, disassembling gear is not the only mechanic science is tied to and even then you can science equipment with less than cap and still gain a lot of resources. If someone see it as a necessity to have a 300% science alt to gain just a little bit more resources from "dead" equipment then it is his choice. Same thing for repair, currently more than 200 is over kill.
Don't necessarily need to be better usage, just more so there is much more reliant on the skill than only few actions. By the way, having to play with other players shouldn't be an annoyance, it is something that players have evolved into that it is just better to make an alt than to ask some player, because making an alt is faster and better and etc. etc. but that wouldn't be the case in a game where you really can't do that and that is something to reach for.
Additionally it's not only about skills being removed, there are some places for skills that could be added when there is some use for them.
So why are talking about this? You think merging it will it a new skill or something?