Supposedly the lorry/train security has been beefed up (along with less vehicles due to Covid or Brexit) which is why they are taking to boats in depressingly increasing numbers. With "taking back control" of our borders, you would think lorry crossings will be more difficult with more checks although that could turn out to be one of those slogans that is more words than action.Just out of interest, what happens when we stop the boats, and they go back to getting into the back of lorries like they did, and no doubt still do (it's just not fashionable to complain about it for the minute)
It is why I have previously suggested creating a standard safe route for those who wish to claim asylum. If genuine asylum seekers know the (fair) procedure that does not involve using traffickers and risking their lives exists, that will cut down on the numbers and undercut the traffickers. After all, would you rather trek across a continent and end up crossing the channel in a dinghy or rock up at the first UK embassy you get to in a safe country, Turkey for instance?
The resettlement schemes we have had like the now defunct Syrian scheme and the still to be set up Afghanistan scheme obviously are selective to those countries and still seemingly inadequate. Numbers seeking asylum in the UK have halved in the last twenty years and as we have seen, we are far from the most popular European destination, our geography actually helping in that case. But obviously there are still significant numbers trying to make our shores in increasingly dangerous ways. Figures show that a substantial majority of people claiming asylum in the UK are granted whether first time or on appeal so presumably are genuine. You will probably never stop those less genuine trying though. But surely a offering a genuine safe and legal way to claim asylum will go a long way to separating them.
The hostile environment policy which has been going for around ten years is clearly not having an affect on those who have a reason or desire to claim asylum in the UK. So why double down on a failing policy? If you want to stop people entering the UK illegally to claim asylum, then surely offering a reasonable legal way would help at least cut the numbers (hopefully substantially) risking their lives to do so.
If not then as you suggest, if you cut down one route, they will find another, possibly even more dangerous route and the problems do not get solved. It really does need a rethink on a European and global scale though, not just the UK although we need to be part of it.