Hateing on Infinite warfare has been popular! So popular most havent even tried it, and the few that had only with the intent of getting all the negative confirmed!
And this game isn't perfect, but its getting better day for day. The biggest problem when it came out was 1. no anti cheat and 2. not really being finished (leader baords and emblem creator etc. not added)
They are about finished now, and while the anticheat isn't perfect to the levels of what we saw in BO3, most of the cheaters are gone by now.
Even though treyarch have better PC support than infinity ward, this game actually works better on PC, this is because the aimassist for controllers isn't as strong in IW as in BO3, and therefor the weapons are made so they are easier to control without, and therefor better for M+KB. Where in BO3 I could only do really good with snipers (that was made without target assist for console) I find that in IW I do a lot better with the AR and SMG than I ever did in BO3, on the other hand, snipers are a little more different, but I'd rather have the bigger variety, and its not like snipers are bad in IW, just takes a bit more skill, and not as easy to "rush" with as BO3.
As for the movement, it is very similair to BO3, if anything its LESS jumpy than BO3. You run out of boost faster, you fall off walls faster. if you want something along the lines of afterburner, you need to use a specific rig (specialist). On top of that, it has Tactical TDM, where you cannot boost jump, and only wallrun for short distances, just to help you get across the map the places wallrun is the only option. And rumors of other "tactical" gamemodes has been mentioned from the developer themself.
So if you hate the modern movement, you can still play, and if you claim you hate it, but still love BO3, something I see a lot of, it so so similair, there is no reason not to like IW.
On top of this, unlike BO3 or AW where variants or new weapons was ONLY obtainable from supply drops, here you can get most by just playing. New weapons you can get by doing relatively simple challanges, most can get one in a day (ie a few hours ingame) and as you play you not only get keys to open supply drops, but also salvage that can be used to craft variants, so if you dont get the variant you dream of in a drop, you can just save up and make it yourself.
As a guy with 1100 hours ingame in AW and never getting the insanity, the only weapon I REALLY wanted, I really enjoy this. Had we had this, I would just have crafted the insanity.
So to sum up. IW is a great game, it is barrels of fun, most cheaters are out, the only thing really ruining the experience. The movement system is very similair to BO3, just a tiny bit less jumpy.
You should really try it, because the playerbase isn't as big at is deserves, and thats a pitty! Why keep playing BO3 where you already have done everything you can do a thousands time, where there is a new great alternative? With new maps and new weapons, and a supplydrop system there is a lot more fair than we ever seen before? Just for this you should support it, because activision has to see we appreciate this, or it will go back to the unfair luck based RNG system again. And if we complain they say "We tried makeing it more fair, you didn't want that"