If you haven't played the others I'd say no. Gears 4 and 5 campaigns are particularly bad and unmemorable. But they do look amazing and when you have nothing else to play on the series X and want to show it off then I guess it's worth loading up. The Campaign makes little sense to a Gears player like myself, so can't see how someone who has only played G1 will get much from it. They don't work in isolation at all.
Wow, now I play Gears every single day. I've only played Gears 5 this year and in 2020. I half agree with what you said but I'm in a minority, Gears fans in the main want TC removed from ever making another Gears game again. I'm quite active in the Gears community as I say I play every day and honestly they have destroyed the Versus, built a terrible half ****ed campaign and certainly not viewed as an asset.
So why do I half agree, the PVE dev's have built the best Gears experience yet. Horde is excellent and the hidden gem is Escape mode. Youtube a couple of escape clips, such a great co-op mode which takes high skill and team work.
New DLC is supposed to be good but I haven't bothered with it yet.
PVE yes, Versus no. Especially in the UK zone it's dead. No one wants to play a one gun game anymore, it's awful imho. If versus interests you, may I suggest arcade mode when you go online. You won't have to worry about Shotgun use only and has far more variety. Horde and Escape are the modes to play and find games.