Rwanda in particular is an odd choice if you are genuinely concerned about the well-being of people who are fleeing persecution, given the UK government travel advice for its own citizens.
It is also a very expensive choice (about the cost of giving them free food and accommodation in an average bit of Hull for over 2 years); but even in its own terms, it does not appear to have changed, nor is it likely in the future to change, the minds of the extremely small number of asylum seekers who have not been put off the UK by virtue of it being a damp sheep-filled rock in the North Atlantic where they will be banned by law from seeking employment.
What percentage of asylum seekers in the UK were eligible for asylum?
Even using “granted” as a proxy for “eligible”, hard to tell as every source I found contradicts all the others, somewhere between 25 and 75 percent.
However, this isn’t the right question, for two reasons.
First: The number you want to compare against is the people whose minds were changed by the latest policy. Given how few people were seeking asylum in the UK even before this, the maximum is already low.
Second: this policy does not improve the expected accuracy of government judgement regarding the legitimacy of any given claim.
E.g. my country had thousands of „refugees“ hoping over border from Belarus last year. Last time I saw statistics, not even 1% was eligible for „refugee“ status. Even skipping the part that, according to international law, refugee is legit for the first safe country.
You can’t because they don’t exist. There is no obligation to seek asylum in the “first safe country.” This is a common trope trotted out by right-wing mouthpieces which is where I’m assuming you got the rest of your “facts.”
For EU, there's Dublin agreement.
Your first sentence is irrelevant because this applies to refugees claiming asylum.