規律 and 規則: necessary discipline and the limit of discipline alone
Compare communal discipline and its stated limitation with a library rule and an explanation of a new rule.
規律: a requirement and a limitation
規律 (きりつ) means discipline or order. 「共同生活では、一人一人が規律を守る必要がある。」 means “In communal life, each person must observe discipline.” Each person must observe discipline in communal life.
「厳しい規律だけでは、自由な発想は育ちにくい。」 means “Free ideas have difficulty growing under strict discipline alone.” だけでは limits what strict discipline alone can achieve for free ideas.
規則: quiet in the library and a new rule
規則 (きそく) means rule or regulation. 「図書館では静かにするという規則を守る。」 means “I follow the rule that everyone must be quiet in the library.” The stated rule concerns being quiet in the library.
「新しい規則を全員に分かりやすく説明した。」 means “I explained the new rule to everyone in clear terms.” A new rule was explained clearly to everyone; no location or agreement is supplied.
Read the scope of だけでは
A need to observe discipline does not establish that discipline alone develops free ideas.
The sentence does not say all discipline always blocks ideas or classify the two words by whether rules are written.
Does 厳しい規律だけでは mean that all discipline always prevents free ideas?
Show the answer and why
No. It states a limitation of strict discipline alone. The separate sentence still says each person must observe discipline in communal life.