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I was talking with my buddy about the difference in suspension. He told me that prior to the 60's 2wd chevys had IFS front suspension and 4wd had leaf springs all around, due to the lack of technology for 4wd IFS.

Is this accurate? Do yall have a preference in suspension?

Thank Ya,
Dave

GM trucks went to independent on 2wds in 1960, 1988 on full size 4x4 (s-10 had independant from the start in '84). It wasn't due to lack of technology, it was more due to durability and ease of manufacture/repair. Back then, most 4x4s were working vehicles used in harsh or rugged areas. They were also a relatively low production option, so tooling up and manufacturing a different suspesion didn't make sence from a dollar standpoint. There were some 4x4s with independant front suspension back then, it was an option on the Willys Jeep pickup and Wagon in the '50-early '60s. It was somewhat of a cross between the later ford twin traction beam and a regulat sla type suspension. It proved to be high maintanance due to balljoint wear and alignment issues. There were also some military vehicle that had not only ifs, but irs as well. The ford Mutt come to mind.
You might be surprized to hear this, but the tortion bar suspension that is used on modern GM trucks actually had its origin in the 1966 Cadillac ElDorado/Oldsmobile Toronado. It was first used on a 4x4 on the '84 S-10 pretty much intact from the passenger car, only the axle center section to allow for a center diconnect. Even the balljoints and shock absorber will swap. the version used in the full size in identical, only larger.
As far as preference goes, I like to keep the suspension that the chassis was designed for in place, possibly with some handling upgrades like anti-sway bars and gas charged shocks.

Your buddy needs to crawl under some old trucks.

Prior to 1960 All Chevy pickups and trucks had straight axle front suspension with leaf springs at all four corners.

IFS on pickups started in 1960 in two-wheel-drive models.

Four-wheel-drive IFS came much later and I don't know exactly what year it was. I believe different weight ratings and models changed in different years. The Chevy Luv was independant front real early, but I don't think any others were until sometime in the 80's.

I think the reasons are more complicated than just the technology. Technology advances when an approach is used enough to require refinement. Until the market is interested in using it, no one is real interested in spending money to develope or refine a technology.

If you look at new trucks you'll see that in the heavier ratings manufacturers have begun going back to straight axles and leaf springs on models that a few years earlier were available with IFS.

Manufacturers try to provide what buyers want.

As for a preference? What am I going to use it for?

I have a 1-ton 4x4 with IFS that seems very usuable and a little rough riding. It would be rougher with a straight axle and I'm content with it the way it is. It does great pulling a trailer, which is what I bought it for.

My wife's car is all-wheel-drive and independent at all four corners. I'd never use it to pull a trailer, but when not pulling a trailer would probably choose it over the 1-ton unless I was dealing with deep snow or water. It rides very comfortably and handles great.

I have a two-wheel-drive pickup with IFS that drives like a big car. Its a more comfortable ride than my straight axle trucks, and more pleasant to drive any distance. These days I never drive it because my kid always has it.

I have several old straight axle two-wheel-drive trucks and when I want classic looks they are my choice.

And I have a rear-drive car with four-wheel independent suspension that I currently drive most days because a Corvette is a blast to drive. Four-wheel independant used to be unusual and limited to sports cars like the 'vette. Now days its much more common because it reduces unsprung weight which improves ride and handling and buyers want that.

What I'm trying to say is that there are good reasons for different suspension types. When choosing a preference its best to start from how you plan to use it and what you want it to do. The various combinations have benefits in different situations.