He's most likely referring to Adaro stealth farming, which is what most players use for quick Warframe levelling. You can easily do a run in 3-4mins, killing 100-150 enemies, but the Larvling and glass enemies will break your stealth multiplier which can be annoying.
I agree, would be nice to have an option to turn off Larvlings. Annoying when I get a Larvling in almost every Grineer mission I run. At least it makes you hold interact to spawn a Lich now, so I haven't accidentally created a Lich in months.