Not exactly correct. If it was 2.4GHz, or higher, it would more than likely have to be LOS. Wifi has a pretty high data rate, but degrades quickly when LOS is lost.
Something low frequency, like 27 or 49 Mhz, would be capable of more than LOS, but 49 is getting up there in terms of becoming more LOS dependent (near HAM 6m band).
Wifi can only hit its highest rating at a short distance, LOS, and no obstructions. Wifi is 2.4GHZ and the 5.8GHz bands. THe only reason it works at longer distances is good error protection protocols, and encoding rate reductions as the ends detect degradation in the data quality.
Many remote cars nowadays are 2.4GHz. Only recently did I buy a toy that still used 27MHz, but it’s a recharger large sized helicopter.
I have a $20 5.8ghz DECT 6.0 cordless phone made by Uniden. Works fine all over the house. Absolutely clear and noise-free. Far better than what one could buy in the 80's and 90's for much more money.
And I don't have to be able to "see" the base station to use it. So, in that sense at least, it's definitely not LOS. Of course, if by LOS, you mean it can't use ionospheric skip or tropospheric scatter, then you'd be right. But those modes are irrelevant to the case at hand, regardless of frequency.
The more modern remote controls use digital technology to encode their signals, much as the DECT phone does. That greatly improves reliability and makes work accidents due to random interference much less likely.