Didn't like the second season
It's all subjective and while some fans liked the second season, I didnt because it was completely different and negative. I agree with one OP who opined that the series should have started with the second season instead of changing from first to the second so dramatically.
Some viewers criticized the first season because while the aliens did dastardly evil, somehow their efforts were thwarted, often just narrowly, with each episode. While the critics thought it boring and repetitive, I liked that angle.
Jump to the second season beginning and everything is a total shock. Instead of our normal, functioning world and society, everything has seemingly broken down and become decrepit. The show always takes place at night. Civilization is in serious decline. Everyone seems broken down to the point of being beggars or street people. Adrian Paul's character couldn't get any information or any help from anyone without paying money. I noticed that every minor character shown in the second season seems to be demanding money for doing anything. Everyone in society is demoralized, depressed, lethargic, lazy, distrusting and concerned only about self. The second season was totally depressing to watch because it showed the aliens were winning subversively. If they couldn't bring down our world with overt terrorism and destruction then causing our civilization to collapse from within was working.
WAR OF THE WORLDS was typical of television series that garnered a lot of enthusiasm and fans but not quite the fanbase numbers that Hollywood demands to keep it going. The popular series, 'Moonlight' from 2011, the 'V' remake, the 'Sarah Connor Chronicles', Kolchak the Night Stalker, are classic examples of tv shows that the public liked and for the most part the critics, but didn't have the massive viewer numbers to justify continuing those shows. Advertisers won't spend the commercial time money if the viewer audience isn't hight enough in the millions and the television networks can't demand the high commercial time dollars if their tv shows don't cut the high viewer numbers. It's all about the money in the end.