How is it hard to get? Let me break it down for you:
1- State of art, most advanced F1 factory building finishing costruction in a couple of months.
Top of the line production machinery, brand new simulator, brand new wind tunnel all under the same roof

2- Honda (current best F1 PU manufacturer) exclusive factory team from 2026
The may not come in 2026 with the best PU out of the box, but their history speak for itself. They will deliver sooner or later and will spend as much as it is needed to be sure they can do so.

3- Financial and exclusive technical parternership with the second richest company in the world
Quoting Wikipedia:

4- Lots of open positions and high salaries
I'm putting this last because it's the result of the previous 3 points, but this is actually probably the biggest motivator.
You can advance your career in a "brand new" team with extremely high target and with a lot of currently vacant positions to apply for.
Simply speaking, if all positions were filled and/or salaries were low, there wouldn't be this "mass hiring".

I think some of the factors you cite are not as attractive as you suggest.
- Yes, all operations under one roof with new tools and facilities, but the same can be said for some other teams.
- Honda PUs may or may not be the best today, but in recent memory Mercedes built by far the best PUs and often Ferrari's have been strong as well. In light of the FIA's aim to equalise PU performance, this is much less important than it once was.
- Re Aramco, having more funding is always better than having less, but (for most teams) under the cost cap it cannot be exploited beyond the top three highest-paid, so it is at most a marginal advantage. Merc supposedly offered Verstappen $150m/yr to drive for them; if they can afford that, they can afford to pay an Adrian Newey whatever it would take. As for an 'exclusive technical partnership' with Aramco, I'm really unsure why that would be more valuable than Shell's partnership with Ferrari or Mobil's with Red Bull.
- 'Lots of open positions and high salaries' - again, what about the cost cap? Last season AMR reportedly had revenue of $290m. How likely is it that, with that level of revenue, they were not already constrained by the cost cap of $142m? Where is the capacity for lots of new positions and high salaries?
A major factor that you do not mention is what it would be like to work for Lawrence Stroll. Some people might love to have the guy as their boss, but Szafnauer said that Stroll (whose technical expertise is in fashion marketing) likes to 'micromanage' the racing team: such interference is unlikely to be helpful. Stroll's behaviour in dealing with his racing driver son has been dubious. If one is to go by his repeated public representations about what was happening at AML (the road car company), I shall not call Stroll a liar, but let's just say that he was 'wrong' a lot.
And then there is the man's arrogance: 'I should be knighted for what I have done.' FFS! 