Boxed text (assuming it's being done correctly/sensibly) is nothing more than the DM would do themselves anyway - an introductory description of an area or event that PC's will be able to take in PRIOR to players asking for particular details or further information. This should be information that a module's author specifically intends to be relayed to players. Any details the author considers particularly relevant should be expanded upon in the full description of the room or events. If the DM is doing things sensibly/correctly, then prior to the players interacting with the module the DM will have read it IN FULL, made notes of what they PERSONALLY feel needs to be related to the players (or NOT given to them as the case may be), and any additions/changes they want to make including just binning it all and providing all their own description and narration.
The only problem I have ever really seen with boxed text is when DM's don't read it ahead of time and assess what it says or doesn't say (which includes myself of course) and make any necessary changes before it ever gets read to players. It's probably especially an issue when the boxed text is setting up a scripted event that a DM would want to run some other way, giving players and their PC's more (or less!) chance to take in information and act/react. It's never (IME) been meant to be a substitute for the DM's own gaming choices and narrative style. If DM's LET IT be that, it's their own fault. DM's have never been there to simply read the adventure AT the players, they are there to interact and generate any and all information the module doesn't as well as change any and all information that a module DOES provide if it's deemed necessary. I don't see that any failure of a DM to understand how a published adventure is meant to be used is the fault of adventure authors, unless that adventure is specifically written and marketed to DM's as a "Newbie's How-To" sort of introductory adventure.
That having all been said, I've seen some pretty lame usage, misuse, and criminal omission of boxed text over the last 40 years. DM's, newb or not, must also not be held responsible for adventure AUTHORS not using it sensibly/properly. The more that any DM DOES have to re-write (or just ignore) of an author's boxed text the more clear it is that any mutt can just write up stat blocks. If an author has particular moods, themes, visuals, etc. that they want to convey in an adventure (and not just buy a list of stat blocks and keyed map) the best way to communicate that is not with bullet points of data, but DESCRIPTION and NARRATIVE that is conveyed in boxed text. If an individual DM then chooses to eviscerate that creativity and substitute their own that's THEIR business. You sold them the adventure. At least a superficial amount of description of places, people and events in a DYNAMIC format and not just lists of data and bullet points, is, I feel, what purchasers are paying for. You can't run the game for them, but you are typically expected to provide prose portrayals of the content that don't USUALLY need to be rewritten or ignored, thus easing burden on DM's in coming up with the adventure idea itself, all the people, places, and events within it, all the relevant stat blocks and game mechanical information, AND (if the DM so chooses to avail themselves of it) initial descriptions.
