Hitman 2 made me give up on the franchise. I paid 90 bucks for it, and because of the time-limited content you HAD to play the game on a fixed bi-weekly schedule or you were fcked. HAVING to play the game for a full year even though you paid ridiculous money for it is just.... I have no words for it.
This caught my attention, as I played Hitman 2 earlier this year (combined with Hitman 2016). My initial reaction was that my experience was very different. But then I remembered that they drip-fed the campaign missions. So early players had little content and were reliant on the Elusive Targets to keep them engaged. This ET content is timed, and I assume what you are referring to Vaderini?
Now though we have the full campaign (8 levels), Sniper Assassin missions (three) and Special Assignments (four), plus they still have the Elusive Target stuff. I never felt that I had to play the timed stuff, and frankly I only have done a few. But maybe that's because the game had all the content released by the time I got around to it. Plus, I bought Hitman (2016) and combined the two games under the 2018 umbrella so it feels like there is a lot of content for me to play even before I count the time-limit stuff.
I really like this game and never felt the way you do about it. I see the Elusive Targets as bonus content that's constantly rotating, but I think if I bought it at release I would have felt the same as you.