I applied for a dev position with a salary range with the higher end fitting my requirements. I checked off basically all of the boxes in the job announcement as I had worked as a consultant for that very company in that same position for several years prior. After interviewing rounds and a programming task, the interviewers were very happy with me and were eager to get me started. However, their offer was in the lower ~20% of the salary range. When I asked for the reason, I was told that they had to cut back costs, so they couldn't afford to pay me more.
So basically, the salary range was just bait to receive applications.
Yeah I assume it will be that you have to have actual numbers, so if no junior software dev earns 250k then you can't post that as upper range, I tried to find info about it, but it turns out it's not EU regulation, only a directive so each member country will implement it's own exact version