Travel is low-margin and sensitive to economic changes (making it risky), which means that travel firms are consolidating. This is certainly true of rental cars.
The high prices you're seeing are a result of many factors, not just consolidation. One of those factors is that rental car companies sold their fleets during the pandemic to stay afloat, and they're now dealing with constant inventory shortages.
This makes sense. With interest rates rising I would guess this affects car loans faster than say home loans so consumer demand may go down. Fleet companies like car rentals could purchase additional inventory to meet the Summer demand since their fleets are simpler configurations. Last time I rented a larger vehicle was 2019 and the price then was $104/day. The SUV we got looked like it had been used on a construction site. Now prices are closer to $200/day.
The high prices you're seeing are a result of many factors, not just consolidation. One of those factors is that rental car companies sold their fleets during the pandemic to stay afloat, and they're now dealing with constant inventory shortages.