I don't look at it as flack so much as just more justification that Starliner, and by extension Boeing, is a failed system and a direct indication of legacy space's inability to compete with the new ideas and ways of development that companies like SpaceX, Rocket Lab, Firefly, etc. are using now.

Boeing talked a lot about how their design and testing processes were inherently better and safer than companies that work through iterative design (like SpaceX). They were given nearly twice the budget ($4.2B) of SpaceX ($2.6B) to develop a similar crewed capsule system. They were expected to have a system up the fastest since their delivery vehicles were already using tested processes and would be essentially coming from previous known effective designs with modern updates.

Yet Starliner's un-crewed test launches so far have had fundamental issues, including a launch that failed to dock to the ISS entirely, and the crewed launch attempts have all run into issues causing scrubs that realistically should have been caught before launch day. They are 6+ years behind schedule on getting a crew into orbit. Meanwhile, the SpaceX Crew Dragon has made 13 crewed flights already. It's taken so long that at least one Starliner trained astronaut was taken from their program, cross-trained on Crew Dragon, and has visited the ISS already before Starliner has even launched their first crew.

The flack isn't about the scrub itself, everyone wants safety, it's about really everything else in the program. This program just shouldn't be having flight scrubs at this point for things other than weather. Especially not something ridiculous like this latest scrub, especially since the rocket it's on is a well-tested mature design. It just makes them look incompetent at this point:

The space agency said the launch was scrubbed "due to the computer ground launch sequencer not loading into the correct operational configuration after proceeding into terminal count."
United Launch Alliance, which manufactures and operates the rockets that launch the spacecraft into orbit, "is working to understand the cause," NASA added.