If memory serves, it was Air Marshall Slessor (or another senior officer) who remarked, in relation to the Polish contribution to the BoB, words to the effect that but for the contribution of Polish aircrews he would hesitate to say that the outcome would have been the same.
You can, of course, provide a link for this, can't you? It's just that I prefer not to take the word of a racist liar and, if memory serves correctly, you are a racist liar.
If we accept this hypothesis (which effectively says the BoB would have been lost without help from the Poles), and if we accept that the loss of the BoB would have precipitated the fall of GB, then yes, England would have been defeated.
Firstly, saying "I would hesitate to say something" does not mean "I would not say something". The word 'hesitate' means 'to pause temporarily'; it does not mean 'stop' or 'decide not to'. But of course to a liar like you, 'hesitate' means 'not'.
Secondly, even if the BoB had been lost, the chances are very much that Operation Sealion would have failed. Adolf Galland, commander of Luftwaffe fighters at the time, observed the invasion plans were not serious and that there was a palpable sense of relief in the Wehrmacht when it was finally called off. And he was not somebody known for not speaking his mind. You might want to note that Operation Sealion was called off
during the BoB.
In that regard, one could even suggest that the detractors of the Polish contribution have the burden of proving that England WOULD NOT have been defeated but for the Polish contribution, rather than the other way round. In other words, if you enter a scrap to help a friend who's getting pounded by an enemy and your friend prevails, the facts stands for themselves that your friend would have been crushed but for your help - res ipsa loquiter.
Even by your standards this is hysterical! Most people would observe that Poland entered the fight (i.e. WWII) on 1 September 1939 when Poland was invaded by Germany. But in your parallel(ish) universe, Poland actually entered the war in 1940 when Britain was "getting pounded" by Germany! Superb stuff dear boy! You haven't written anything this good since you claimed that it's not racist to use the word "Paki"!
But to use your own 'logic', detractors of the British contribution have the burden of proving that all Poles WOULD NOT have been exterminated but for the British contribution. As you yourself put it: if you enter a scrap to help a friend who's getting pounded by an enemy (and Britain did enter WWII to help Poland) and your friend prevails (according to your IPN, the Polish flag did fly over the Reichstag), the facts stands for themselves that your friend would have been crushed but for your help.