Why have a game environment? Why bother mentioning the furnishings of a room or describing contents of anything?
Sometimes it is nice to describe a room in rich and flavorful detail. Sometimes you don't want to wait twenty minutes while the players ask for quotes from every book in the evil wizard's library while searching for a clue.
In my games, I tend to try and accomodate both styles at the same time. You can describe the room, and if a player actively says they are looking in the right location, they find the treasure. If a player doesn't do so, but says their character is searching the place, and rolls well, then they can also find the treasure.
DM: " You find a small room. In the room is a....."
Rogue: "Yeah yeah yeah, whatever. I search the place top to bottom....I got a 35! "
DM: " you found a ring worth 1500 gp"
Rogue: " Sweet. I take it and leave."
DM: " No problem".
Yeah, I'm gonna call BS on this example. You could just as easily have that search check reveal that there is a pillow that is unusually heavy, and then the player has to make the call whether to open it up or not, and how.
More on the actual point - again, this isn't anything new to D&D. You are complaining about this, using specific "Diablo-style" imagery, as though WotC is somehow making this into a video game. But this example shows that D&D has long been able to reduce searching a room to a dice roll, or to Detect Magic, or whatever.
Regardless of which method is used, the fact that I can now make an Arcana check to sense a magic item in a pillow has
nothing to do with an example in which the DM just decides that by detecting magic, I've automatically decided I will tear open the pillow and take the item without even informing me of doing so, and then later visit consequences upon me for such an action.
As you can see, just throwing out a DC to speed things up without so much environmental interaction can lead to all kinds of assumptions. What does finding a well hidden object mean? How much impact does finding it have on the rest of the game?
I just don't see any way in which that skill check and a simple DC is tied to the DM making a ludicrous assumption about a player's actions. If there
is a genuine need to know how a player is searching, the DM to ask to try and know more. If the player succeeds on a search and finds something out of place, there is no reason the DM shouldn't ask how they want to proceed, rather than making those problematic assumptions.
The skill of the character to find almost anything can cause issues if the specifics are glossed over. Telling the player to roll then informing him/her of success tells us nothing.
So you genuinely feel that if I, as a DM, have a player announce that he is searching a room, he rolls a Search check, and I think inform him of whatever interesting things he finds, I am doing something wrong?
Look, I have NO PROBLEM with a game where players describe actions in more detail. I think that is a reasonable and legitimate style of play. But you aren't trying to convince me that is acceptable - you are trying to convince me that is the only way to play, or that doing anything less is video-gamey.
And that's not cool. That's level of elitism is an attitude that is far more of a bane on the hobby than anything WotC has ever done.
Lets say the DC for a general " I search" was 25 but actually mentioning examining the pillow (which had a detailed description) lowered the DC to 20 or even 15 which would reveal that there was something small and not too fluffy inside. The player then decides what becomes of the pillow.
As I mentioned above, that's my preferred method - taking it even a step farther, actually, as if a player looks carefully enough they might find something without needing to roll at all.
But that doesn't mean there is anything wrong with them not being able to notice, as a player, what unusual object they need to investigate, and wanting to roll the dice and rely on their character's capability to find something.
More than that, let's bring the point back to your actual complaint - the ability to do so not just with physical searching, but with Detect Magic. Where is the problem with this? I've seen people using Detect Magic to find treasure for years. I've seen it mocked as a classic D&Dism in Knights of the Dinner Table. So why the need to remark on it as something new that WotC is doing to turn D&D into a video game??