LuCI with embedded Lua interpreter

Installing and Using OpenWrt
1

I found/followed this guide on my Linksys WRT3200ACM running OpenWRT 19.07.6 and it was a night and day difference from the "stock" behavior/performance of running LUCI out-of-process from uHTTPD.

I understand that it is faster, and it is demonstrably so, but my question is:
If this is so much faster, why isn't this the default in configuration for OpenWRT? What risks have I taken on by following this guide?

Thanks!