I agree with you that we need better data to draw firm conclusions.
We don’t know their baseline that they used to determine that Delta is 46% more likely to reinfect.
Those articles that you posted clearly state that “Reinfections remain a rarity though, accounting for only 1.2% of the 83,197 cases analyzed.”
If, as cited in the articles that you posted, reinfection rates are 1.2%, then they may have started with a baseline of .77% with Alpha to arrive at the 1.2% after a 46% increase.
But, as you say, take it with a grain of salt. I agree with you that we need better data, and more time to analyze the data to understand what is going on.
The articles that you posted also state that, from June 21 to July 19, 30% of COVID patients admitted to the hospital in England had been fully vaccinated.
That doesn’t seem good. Hopefully our vaccines are better than their Oxford vaccine