Will a 2x with a clutch RD be just as effective as a 1x with a clutch and narrow-wide chainring on an mtb? I am continuously dropping my chain on my enduro mtb rides (currently 2x). The rear derailleur that my bike is currently running is a deore non-clutch. 

My chain will normally drop after riding rock gardens, jumps, and drop offs.

My friend  says that even if i get a clutch version of my current derailleur I will still drop my chain and that I should just convert to 1x. But a 1x conversion is more expensive and will lower my gear range. So I would like to know if a clutch 2x will have the same effect?

Note: My bike was new 2017 but has had hard use, the bike is a feul ex 5
It will help 2x, though 1x is going to hold chain better. I think you'll still see an improvement with a 2x setup due to added chain tension. When I upgraded the drivetrain on my full suspension to use a 10spd Shimano Deore clutch derailleur it didn't drop chain nearly as much if ever. Make sure you have your chain shortened to the appropriate length as that's one of the biggest factors causing chain slap and jumps is having a chain that's too long. 

A 1x would likely work better if you switched to a narrow/wide chainring that prevents jumps though. I almost never drop a chain on the 1x setup with a race face narrow wide ring. The front chainring does a lot to stop the chain from slipping off due to the tooth profiles that really keep the chain engaged. I'm running a cheaper 10 speed setup on my hardtail with a sunrace 11-42 casette with a 10spd sram x-9 clutch derailleur and it works very well and was a cheap upgrade vs a whole new 11spd.