With the recommendation of stopping every 90 minutes on long car trips, is there a certain amount of time you should have the baby out of the capsule for each time you stop? For example should this be longer periods of time if you've got a longer car trip?

Red Nose has no specific recommendations for time frames when travelling with baby in a car safety device but has the following information.
Once the car journey is over it is very important that you remove baby from the car seat or capsule, even if this means waking baby, because it is not safe for baby to spend long periods in car seats, capsules or infant seats.

Research has shown that:

babies left in a sitting position for a long period of time may be placed at increased risk for sudden infant death.
car or baby seats may cause baby’s neck to flex forward which may block baby’s airway not allowing airflow
falls from car seats used outside of the car as infant carriers are common, often involve children unbuckled in their car seats and represent a significant source of head injury for baby. Never leave baby in carriers on shopping carts, counters, or other high locations
https://rednose.org.au/article/are-there-recommendations-for-car-seat-or-baby-seat-use

Most safety organizations would follow travelling advice for all when driving long distances - take a break every 2 hours.