If you think syntax highlighting is what's slowing it down, then you need to try to load one of the problematic files with vim -u NONE. That command tells vim not to load any config and thus vim launches in vi compatibility mode. If it it's still slow, then it's not the syntax highlighting and the problem is elsewhere. For example, vim doesn't take too kindly to files that are absurdly huge (>5MB) or have absurdly long lines (>10K columns). But the thing is, that in itself is way better than all the other text editors, which choke on files much smaller than the ones vim chokes on. You should isolate the problem before spreading something like this; you might be spreading misinformation.
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If you think syntax highlighting is what's slowing it down, then you need to try to load one of the problematic files with
vim -u NONE. That command tells vim not to load any config and thus vim launches in vi compatibility mode. If it it's still slow, then it's not the syntax highlighting and the problem is elsewhere. For example, vim doesn't take too kindly to files that are absurdly huge (>5MB) or have absurdly long lines (>10K columns). But the thing is, that in itself is way better than all the other text editors, which choke on files much smaller than the ones vim chokes on. You should isolate the problem before spreading something like this; you might be spreading misinformation.