Does Brussels Airlines gate-check luggage on small planes?

I’m not sure I fully understand your question? How does your itinerary look like? Are you transferring in Brussels? If so, why don’t you just check in your bags at your departure airport al the way to your final destination. ? If you do that you don’t need to claim and recheck them in Brussels.

Sorry! I am flying from Canada-->Brussels-->Marseille. I am meeting my brother at Marseille airport. I would prefer to meet him at his gate where I could take a nap, as he arrives after me, so I would prefer to keep my bag with me, rather than check it to my final destination. Since the flight from Brussels-->Marseille is on a small plane, I'm wondering whether this airline gate-checks bags that don't fit in the overhead bins (so that you can pick them up planeside in Marseille) or whether it checks bags only to final destination (baggage claim in Marseille).

“ I'm wondering whether this airline gate-checks bags that don't fit in the overhead bins (so that you can pick them up planeside in Marseille) or whether it checks bags only to final destination (baggage claim in Marseille).”

When you gate check an item it doesn’t necessarily mean that you can pick it up planeside. They usually only do this for strollers. All other items that were checked in at the gate, usually end up on the bagage carrousel.

Small plane? Brussels Airlines operates Airbus A319's on that route. Not exactly a "small plane" since it holds about 120 passengers.

Are you on a different connecting flight to Marseille?

I'm not sure. They just sent an email in advance

"Due to limited storage space in the cabin, you may be asked to check your hand baggage in at the gate, even if it complies with our baggage policy.

For your own comfort and to assist in enabling an on-time departure of your flight AC6362 to Marseille on 03Mar2023 we recommend that you check your hand baggage in free of charge and without any liquid restrictions at our check-in desks (max 8kg, 55x40x23cm)."

Easiest airport rendezvous, almost everywhere: At your destination hotel. Marseille Provence is an efficient operation and you can look up their good website to see what might be mutually suitable inside. But airports are not designed for lingering.

Due to limited storage space in the cabin, you may be asked to check your hand baggage in at the gate, even if it complies with our baggage policy.

This is pretty much true on any airline. More people are carrying on their luggage, planes are full, and the overheads on most planes aren’t big enough to store the largest allowed carry-on for every person on a packed plane. On my last overseas flight on United they announced that 20+ people would need to check their carry ons because the plane was completely full and asked people to prepare by removing medications and anything needed for the flight.

If you have a bag that meets the size limit, the requirement to gate check is pretty much beyond your contol unless you have a premium ticket (e.g., business class). I’d suggest just being prepared for the possibility.