Why are Selenium WebDriver tests suddenly running slowly?

Question

selenium

Hello,
I recently encountered the following non-trivial task. There is a group of tests (about 40 pieces) that use Selenium WebDriver + ChromeDriver. Until recently, they took a total of 50 minutes to complete. Just a week ago, the test execution time doubled, and today I was generally disappointed by the fact that the tests take 2 hours and 30 minutes to complete. The tests did not change, the driver and browser were updated to the latest version just in case, but there was no result. I run on several different machines, the execution time is equally huge.
I installed dotTrace, looked at what actually eats the execution time of scripts and was surprised. It is Selenium WebDriver methods like FindElement(s) and GetText (for example) that take the lion's share of the execution, went down the chain in them and saw that it was HttpResponse. As I think, most likely something is junk in conjunction between Selenium WebDriver and ChomeDriver. At first I thought that perhaps the Front-end was slowing down somehow and doing something in the background, blocking the DOM, etc. But I'm not sure, I looked in the browser, I did not find anything like that.
Googled the problem, only found the only solution is to try disabling Proxy in ChromeOptions. Did it, didn't help.
Now, as for the website itself. Written in BackboneJS. According to the developers, they did not change anything radical.
It seems to have written everything I know. The question is, has anyone encountered a similar problem? What could it be and where to even dig?
Thank you.