if a person becomes bound by this routine, it sort of defeats the purpose
ーEven though I decided on a daily routine to have a more fulfilled life, if a person becomes bound by this routine, it sort of defeats the purpose, so I don't think I need to follow this routine so closely.
「もっと充実した生活を送るために日々のルーティンを決めたけど、このルーティンに縛られたら本末転倒だから、このルーティンをきっちり守る必要はないと思う」
if a person becomes bound by this routine, it sort of defeats the purpose で「このルーティンに縛られたら本末転倒だ」
to become bound by で「〜に縛られる」
ここでは to defeats the purpose を使って「本末転倒」を表現すると良いと思います。
ご参考まで!