BBEdit is my weapon of choice for reading massive log dumps and database dumps for support at $DAYJOB. It does not seem to ever choke no matter how many hundreds of megabytes if text I need to plow through.
BBEdit is a big misfit for me and how I use editors. It’s great at transforming text and zillion of other features but I get my work done in VSCode or PyCharm. My true preference was Atom. RIP
Even with this all, I still install BBEdit on every device I can.
Other apps are much better at large files. The APFS filesystem has a maximum file size of 8 Exabytes and plenty of other text editors can handle file sizes that large without any issues.