loading screen pops up often

hello,

i have an iphone 8+ and i’ve had it for about 4ish years. i’ve had no problems with it at all, untill recently. over the last couple years sometimes a loading screen would pop up and i would think nothing of it. but now; when i open my phone (with thumbprint) i’d say about 70% of the time a loading screen pops up, and also when i exit apps a loading screen pops up, this screen can last from 20s-3m. this happens so often now it’s getting on my nerves. sometimes even it just randomly shows the loading screen. i understand my battery health could be dying (it’s at 78%) and just a btw this started yesterday. i am going to upgrade my phone in the next couple days but i am still curious and others may have the same question. thank you, have a nice day.