Looks nothing like either. Closest thing it resembles is the bisexual flag.
If Nike have reiterated that it's nothing to do with any of that, but to celebrate the last and only England team to win anything, I'm perplexed as to why the outrage doesn't stop there. Unless the implication is they're lying and are secretly trying to turn everyone gay?
In which case, nobody would have even known about the resemblance unless they made such a big fuss about it in the first place. Can't say most people are super well versed in the various pride flags. People would have heard "1966 training kit" and said oh okay and kept it moving. Because it's a bloody football shirt, and there are countless more important things in life to spend calories on.