We can't sign up a large squad. There are financial fair play rules to prevent this;

League One and League Two clubs will be limited their squad size to 22 players for the 2020/21 season.

This will be reduced to 21 and 20 in subsequent seasons (2021/22 and 2022/23 season respectively).

Players aged under the age of 20 are exempt from these restrictions.

https://footballleaguefc.com/league-one-and-league-two-squad-salary-cap-all-you-need-to-know/#:~:text=League%20One%20and%20League%20Two%20clubs%20will%20be%20limited%20their,are%20exempt%20from%20these%20restrictions.

What do we want a reserve squad full of has been's for anyway?

The whole system has changed so that you have development squads for younger players.

You don't want a second string of 25 to 35 year olds playing reserve team football...