If that were correct it would be based on market cap not stock price

It's likely just because for legacy reasons exchanges can't handle fractions of a cent, so below $1 the price becomes too discrete

surely price manipulation is a function of the market cap, not the share price.

again, people don't buy stocks with actual physical cash. theres no reason why we are tied to whole pennies. a 2c stock could rise or fall 1% in the same way as a $2 stock could.

plus lowering the number of shares in circulation isn't going to make it less susceptible to pump and dumps.

finance is populated by a lot of extremely well paid people, I can't believe everyone has a blind spot around 'bigger arbitrary token size == better'

As long as stocks are primarily owned if not traded by humans, I do think its a good idea to have a lower limit on the price. There's a sweet spot, where humans have an ability to discern price movements. If there are too many zeroes before or after the price, we can't tell if the price moved and what it means. So we don't have $45000 stocks or 45 cent stocks.

But on my dealers website I can look at price history and it will tell me the price history and percentage for the past day/ week/ month / year.

To put in bluntly. If you're letting human factors get involved your doing it wrong.