I’m a big fan of LunarVim, but handling large files out-of-the-box is not a great experience. Observed in both lvim, and neovim with my own config. I’ve found myself leaning on helix in those cases - quicker than screwing with either config, or running vim -u NONE.
LunarVim is my daily driver, but Helix is screaming fast compared to it in many cases.