The recurring host -- who was back for yet another gig this year -- kicked things off Sunday by actually running a little bit late ... but once he got going, he was ready to make some jabs and crack some jokes ... most of which landed fairly well with the star-studded crowd.

Jimmy mentioned the fact that Margot Robbie and Greta Gerwig were snubbed this year -- chiding the audience who seemed to agree, since a lot of them are voters -- and he even poked fun at Robert Downey Jr. at one point ... referencing his previous drug use.

Jimmy referenced an old dog-themed movie RDJ was in -- and said if he was ever to remake it ... he know the perfect candidate ... highlighting the dog from 'Anatomy of a Fall.'

The guy hopscotched around in his monologue, but eventually landed on the SAG and WGA strikes -- which consumed much of entertainment in 2023 ... and which created a lengthy work stoppage in Hollywood as labor union honchos and studio execs negotiated new deals.

Jimmy sounded sincere in shouting out everyone who remained on picket lines through that difficult period -- but, of course, he eventually gave kudos in a funny, backhanded way.

Check it out ... Jimmy says the strikes taught everyone a good lesson about what they were made of -- namely, a lot of guts ... even though he said no one would ever be able to pick up a shovel. Jimmy also used a lot of colorful descriptors in patting everyone on the back.

You gotta see it to understand what we mean ... it was both graceful, and pretty insulting.

Jimmy ended on a high note, though, when he brought out a bunch of crew members who work behind the scenes ... saying he appreciated their support through the strikes. Looks like everyone else felt the same way -- 'cause all the production people got a standing O.