This may and may not even work for you. If you reset, then proceed to install all your apps again, you may not see a change. Here's an analogy to help if needed.
Let's say you're running out of storage space and decide to uninstall everything. If you then go and install everything again, you'll again run out of space. In the case of a laggy phone, you could be running out of processor "space" (demanding more operations than it can smoothly handle), or perhaps memory/RAM. Those same problems could occur after a reset unless you make some changes.
My first suggestion would be to uninstall unnecessary apps to limit the demand on system resources. Clearing app caches may also help, but may also only be a temporary fix as those cache files are rebuilt. Adjusting apps to limit background processes, such as increasing online sync times , also help.
So I'd look into those options and see if it helps any. I try to save factory resets as a last resort.