君臣不得不尊﹒父子不得不親﹒兄弟不得不順﹒夫婦不得不驩﹒少者以長﹒老者以養﹒故天地生之﹒聖人成之
i think that there's severe misinterpretation.
the text is to emphasise the importance of saint's etiquette (聖人之禮法)
the scanned copy in internet archive: https://archive.org/stream/06072285.cn#page/n45/mode/1up
there's a remark "不得謂不得聖人之禮法" and "驩與歡同" after the verse "老者以養"
the orthodox way of interpretation should be:
君臣不得不尊
--> 君臣﹒不得聖人之禮法﹒不尊
[in the relationship of] a ruler (君) and his minister (臣), [if] saint's etiquette (聖人之禮法) is not (不) learnt (得), the minister would not (不) respect (尊) the ruler.
in this type of relationship, respect (尊) is one way only, a proper behaviour performed by a minister (臣, aka the lower strata one) to his ruler (君, aka the upper strata one).
夫婦不得不驩
--> 夫婦﹒不得聖人之禮法﹒不驩
[in the relationship of] a husband (夫) and wife (婦), [if] saint's etiquette (聖人之禮法) is not (不) learnt (得), the wife (婦) would not (不) please (驩) her husband (夫).
in this type of relationship, please (驩) is one way only, a proper behaviour performed by a wife (婦, aka the lower strata one) to her husband (夫 aka the upper strata one).
the remark stated 驩 (u+9a69) is equal to 歡 (u+6b61). i would interpret it to "please", as a verb.
about how can a wife "please" her husband, you may imagine it freely :)
have fun 😼