Some facts on migration and numbers compared across European Countries. This is from 2019 when we were still a member.
https://www.infomigrants.net/en/post/21810/seeking-asylum-in-europe-in-2019-facts-and-figures
The headlines if you can't be bothered to read:
Roughly 473,000 first time asylum applications between Jan & Sept in 2019 - extrapolated to 630,000 for the whole year.
From Jan - Sept, applications by top six country as follows:
Germany: 111,000
France: 87,100
Spain: 80,000
Greece: 47,000
UK: 32,000
Italy: 25,000
All bar Greece are the most populous countries in Europe and in fact Greece and Malta has the most first time asylum applications per capita in Europe.
The Dublin Regulation that Essex refers to is explained here:
https://en.wikipedia.org/wiki/Dublin_Regulation and has been around since 1990 in various forms, but it is about a mechanism for identifying the country responsible for examining an application for asylum and provides a mechanism to transfer the applicant to that member state.
Hungary withdrew from it in 2015 because it said it was overwhelmed with applications for asylum in it's own country already (60,000 in 2015). The response from Germany and Czech Rep was to process more applications.
We withdrew from that when we did a Brexit I'm afraid.
Living in Germany is obviously almost 4 times more attractive than living in the UK if you're an asylum seeker...but don't let small matters such as facts get in the way of a good bit of jingoistic nonsensical/ill thought out ranting.