It's extremely difficult to find any sort of graduate job right now, international or not. You only have 18 months post-graduation to secure a job and hope and pray that you can then stay on a Skilled Worker visa which is either £25,000 salary for education/healthcare, which is doable. But it's £41,700 for most other jobs which unless you're going into high finance or land a grad scheme at a bank, probably won't happen in 18 months.
Then factor in the additional costs to a business to sponsor an international student instead of picking one of the thousands of home grads they do not need to do that for.