Wow, that's an interesting perspective.
Meanwhile, Big tech (pre-2022) went to pretty extreme lengths to keep tenured employees around because of all the knowledge they'd built up which made them valuable to the company.
But whatevs, you do you. I'd advise you to only hire contractors if you want people to stay less than a year.
And it's worth noting that you appear to be responding to people who are in German speaking countries, where 3 months notice is standard. Other parts of Europe are not like this, and in Ireland you can fire as per the US for the first 6 months/year, and only need to pay redundancy if they've been there 2+ years.