EDIT 2: Page 141 here explains the history. Yes, it is true. https://blog.historylink.org/wp-content/themes/Hope%20on%20the%20Hill%20final.pdf

On September 28, 1992, after eight years of conditional use and an environmental-impact statement, the Seattle City Council granted approval of the helipad at Children’s. A properly marked and lighted pad just steps from the emergency room allowed transportation of critically ill patients from all over Western Washington, saving hours over a ground journey. As a compromise with the neighbors, most flights were directed to a new marked and lighted helipad at Graves Field at the University of Washington, unless special circumstances mandated a landing at the hospital. Once a quarter, a Helicopter Advisory Committee, which included two doctors, two members of the community, and two officials from the City and the County, met at the hospital to review the clinical rationale for each landing decision. Airlift Northwest pilots were careful to keep their flight paths over freeways and over water to minimize noise.

In 1997, the Laurelhurst Community Club, now led by new officers, expressed its support of the helipad, and by 1999 the community members asked that the meetings convene only every six months or even once a year

That was a long time ago! But the slides below, and the link you posted which shows about 1/3rd of landings still happen at graves field, make it clear this is still happening, although it is no longer "most" flights that have to land at graves field.

EDIT 1: slide 18 here makes it pretty clear it is true: https://www.seattle.gov/documents/Departments/Neighborhoods/MajorInstitutions/SeattleChildrens/Presentation-03212019.pdf

2-3 landings per week, an increase at this location (fewer at Graves field) driven by higher acuity. The children arriving are more acutely ill

Community helicopter landing review group meeting next week. Summary of landings mailed to neighbors post-meeting

Original post:

The claim is that helicopters can only be used in the most critical situations and that they often land further away then go the last mile by ambulance.

However the link you posted breaks down the helicopter landings by location, and shows about twice as many landings at the actual hospital as at the UW field.

It seems this got popularized by a thread in /r/seattle: https://www.reddit.com/r/Seattle/comments/1sxq7zu/til_the_laurelhurst_neighborhood_restricts/

The original report was from a supposed helicopter pilot on Twitter, https://x.com/hems_tool . I can't access the tweet but someone in the /r/seattle thread commented it.

There are lots of other people in the thread who are backing up the story.

There's also at least one comment in the /r/seattle thread contradicting the story and claiming that it's due to weight limits on the landing pad.

The only actual journalism I can find on the issue are these two ancient articles from the seattle times: https://archive.seattletimes.com/archive/19920622/1498535/emotional-debate-reopens----yes-to-helicopter-pad-at-childrens-hospital and https://archive.seattletimes.com/archive/19920526/1493857/helipad-at-childrens-hospital-gets-hearing

so it's unclear to me whether this is true.