My previous employer stopped hiring in the EU (except for the UK, where they were based, and South Africa, where the CTO was from) because the labor laws there made it too difficult for them to fire people, which was a particularly troublesome for them as they had almost quarterly layoffs. They switched back to hiring in the UK and US where there are fewer worker protections.
Does the UK really not have labor laws as strong as most countries in the EU? It's not like you can't fire people in EU, you just have to have an actual legitimate reason to do so, exactly because doing quarterly layoffs is absurd and shouldn't be tolerated by anyone.
Maybe he should not hire people and then fire them after 3 months? Could it be that your previous employer is a terrible employer?