If people are reluctant to let younger people into government then it could affect the ability of future leaders.
参考译文：如果人们不愿意让年轻人进入政府，那么这可能会影响未来领导人的能力。
let younger people into government属于“let +宾语+宾语补足语”用法“let sb into +名词”让/允许某人加入/进入“某个组织机构/某个地方”
let允许/让…进进入let sb/sth into
I had to get up at seven o'clock this morning to let them into the building because they had lost their keys.
今天早上我不得不7点钟就起床开门让他们进楼，因为他们把钥匙弄丢了。
I let myself into the flat.
我自己开门进了公寓。