I too thought VSCode's being web based would make it much slower than Sublime. So I was surprised when I found on my 2019 and 2024 ~$2,500-3,000 MacBook Pros that Sublime would continually freeze up or crash while viewing the same 250 MB - 1 GB plain text log files that VSCode would open just fine and run reliably on.
At most, VS Code might say that it has disabled lexing, syntax coloring, etc. due to the file size. But I don't care about that for log files...
It still might be true that Visual Studio Code uses more memory for the same file than Sublime Text would. But for me, it's more important that the editor runs at all.
Polar opposite experience for me. I mainly use vscode, but I need sublime to open anything big.