The Empire Strikes Back received mixed reviews initially when it was released. Over time it’s now regarded as one of the better entries of the saga. I think it will be the same with The Last Jedi.
It already is regarded as one of the better entries in the saga. Metacritic has it as 85% positive from critics…
http://www.metacritic.com/movie/star-wars-episode-viii---the-last-jedi
I think its also a fair point that ‘time’ may allow opinions to shift, particularly as it is a middle film of a yet unfinished trilogy. The weird ‘Mary Sue’ reactionary stuff that Adywan just alluded to will also hopefully become a relic of the past, and let us hope that in ten years from now people will be more accepting of diversity and female leads.
There appears to be some disparity between the rating given by critics, the general audience, and fans. I don’t think that observation is in dispute. So, while critics have generally praised the film, the reception among the general audience and especially fans appears to be more mixed. The imdb score of 7.4 would place the film in 7th place in relation to the nine films that have been released. Reception among fans, as indicated by various audience polls on the TFN boards, show the film is either near the top or bottom of the rankings.