144 ---> 240hz is basically the last tiny blurriness of a fast moving scout or flying soldier goes away thats what I noticed but its not nearly as significant as 60-> 144hz.
144hz minimum is honestly just the esports industry standard now, even the normies are getting their 120hz TVs and fucking smartphones
however 144hz definitely made my DM better but i think it had an even bigger impact on my movement, everything becoming so much faster and smoother, I could see projectiles clearly and quicker. another thing, ghosting and screen tearing is huge if you had a potato monitor like me, and getting a 144hz removed that almost completely
i could be wrong but not sure if it matters to have 1-2ms response time on the monitor, idk if helps too but a lot of people told me it did