Firstly, you should note that they are no longer ‘asylum seekers’ but ‘illegal immigrants’. The Tory scum already passed laws that say any entry to the UK without permission is illegal. Claim your asylum before getting here (except that the Tories have removed all methods for doing so) and if you come from a safe country (99% of them now arrive on ‘small boats’ from France) then claim asylum there.
Why Rwanda? They wanted to emulate the Australian model and in Rwanda they found a country dumb/greedy/corrupt enough to take their money. They claim the threat of deportation to Rwanda will entirely deter all those in small boats and destroy the people-smugglers’ business model.
They have now spent or will spend some £290m on Rwanda. They spent (IIRC) of the order of £65m with the French to deter and intercept the small boats before they leave France. Can you see their priorities here? (Something about cruelty and the point.)
Meanwhile UK’s legal migration numbers ballooned to in excess of 700k per year for the first time and the small boats 'invaders’ (TM Suella Braverman - dumb as a brick and very, very nasty, but for whom it is all a performance to get the leadership) are IIRC less than 20k (or of that order of magnitude).
Basically, it is all performative blue wall appeal to the lowest common denominator economically oppressed voters with some red meat rhetoric. And his decision to bring small boats front and centre, together with Rwanda (he inherited the Rwanda policy and could have quietly dropped it like he dropped other policies he inherited from Boris Johnson) means that his downfall, either personally before an election, or politically as a result of the next election, is entirely all of his own making.
This is a man who is basically a banking technocrat and who is utterly useless at politics - even the kind his party pursues. The people who are against immigration (‘taking our jobs and houses and using our NHS, etc’ won’t be mollified by a few dozen people ending up in Rwanda, if they ever do.
ETA, that said, about Rish! Sunakered (copyright John Crace of The Guardian whose take-downs of the PM are a regular fillip), and his political incompetence, the Tory party is now unleadable. A leader would have to have a magic touch (guaranteed election success prospects, like Johnson used to have, but probably now does not) to get any consensus among the rabble of right-wing fuckwits and vaguely sensible ‘one nation’ Tories and all the other factions. Brexit is the root cause of most of the issues they all disagree about - of our ballooning legal immigration, of economic woes, and so on. When ‘one nation’ Johnson expelled all the sensible centrists from the party when they voted against his dumb Brexit bill, he set the scene for exactly what has happened since and is happening today within the party. The hope is that they will fracture. The one thing Tories have always been best at is unity - not any more. But they may manage it if the alternative is political armageddon. Sunak’s selection of Rwanda as the hill to die on probably brings us close to their political armageddon. OTOH, Farage is definitely eyeing up the option of joining, getting a safe seat after the election and taking over. It’s a toss-up whether the rightish voters will flock to him (like they did to Johnson, a man with similar charm and swagger) or avoid him like the plague.
Hmm - probably time to take this over to the UK politcs thread, once I’ve calmed down. 
(Various edits to clarify/disambiguate.)
