In its current form, an application of a UNISWAP AMM to a parimutuel market without any external content on the market would result in either the AMM showing equal pools for both outcomes, so 2 to 1 odds before fees or odds which are inline with the current pool sizes for each outcome. With these naive event odds, the LPs will likely fall victim to an informed speculator which has a better grasp of the odds of the event. This will result in LPs incurring negative expected value per event to which the protocol could then respond by raising fees to ensure that LPs eventually recover their capital. However, this has the net effect of dissuading new speculators from joining, all else equal. The above case is the result of the AMM being naive to external market context i.e. an accurate indication of the events probabilities.