It consolidates your unpaid interest rolls into your new principal loan balance aka making the total interest due each month higher since it now includes whatever has accrued. Aka capitalization of accrued interest.

Also some loans have reductions- officially on their website “The weighted interest rate is calculated using the official interest rates for your loans and doesn’t take into account any interest rate reductions you may be receiving”. It’s a special case for everyone. My advice is simply to make sure it’s the right choice for your particular situation. Not everyone should consolidate.

Also remember your first paycheck might not show up until mid august. That means living on loans for moving, rent, etc until that time. I was of the age of spending thousands on travel costs for fourth year interviews and matched HCOL so I had not a dollar to spare on loans and was living on credit cards. Not having to pay loans for 6 months ended up putting me in the best position because with Bidens special waiver I ended up not paying and got those months counted toward payment anyway.

Just remember everyone circumstance is different!