In this context, "the man" refers to large corporations or established institutions that represent authority, power, or the mainstream business world. It typically conveys the idea of conformity to established norms or systems. So, "getting a job working for 'the man'" implies becoming an employee of such a large corporation or entity.
https://www.quora.com/What-is-the-definition-of-working-for-...

في السياق الذي ذكرتَه، يمكن ترجمة مصطلح "the man" إلى العربية بعدة طرق حسب المعنى المقصود:
"رب العمل": وهذا هو المعنى الأقرب في سياق الحديث عن رواد الأعمال الذين قد ينتهي بهم الأمر بالعمل لدى شخص آخر بعد فشل مشاريعهم.
"السلطة" أو "النظام": وهذا يعطي معنى أوسع يشير إلى العمل ضمن إطار مؤسساتي وقيود قد تحد من حرية ومرونة رائد الأعمال.
"الشركات الكبيرة": وهذا يعكس التضاد بين الشركات الناشئة الصغيرة والشركات الكبيرة ذات الهيكل التنظيمي الضخم.

English term (edited): \"the man.\"

I rather think to be able to safely determine an appropriate translation for "the man" here, we definitely need to get more contextual information with regards to what exactly is being described and perspective of the author towards it.
"The man" can easily refer to the Alpha male, i.e. the one who is stronger and greater than others, deserving praise and admiration, as it can also stand for a figure of authority and oppression or pejoratively relate to the entire state apparatus.

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https://en.wikipedia.org/wiki/The_Man :
"The Man" is a phrase used in the United States to refer to figures of authority, including members of the government. Though typically used as a derogatory connotation, the phrase may also be used as a term of respect or praise. The phrase "the Man is keeping me down" is commonly used to describe oppression, while the phrase "stick it to the Man" encourages civil resistance to authority figures.[1]

القصد هو انه سيكون عبد تحت سلطة رب العمل المتسلط السيد الظالم الغشوم وهكذا

the man = هنا تعني صاحب سلطة ولكنه متسلط
سواء كان عن الحكومة او جهة سيادية او صاحب شركة ولكنه غشوم مضطهد لموظفيه

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Note added at 7 hrs (2024-05-05 21:21:26 GMT)
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or go out of business and get a job working for "the man."
اترك هذا المشروع/اقفل مشروعك/ عزل شركتك واعمل كعبد "موظف" في احدى الشركات
او اعمل بوظيفة لا تسمن ولا تغني من جوع

القصد عمله تحت سلطة اي شخص آخر سيكون لا فائدة فيه ولا يوجد هناك فرص للتقدم او الغنى

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Note added at 2 days 10 hrs (2024-05-08 00:34:42 GMT) Post-grading
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بل هو المعنى المراد من النص هو إما تكون حراً صاحب شركة وناجح في مشروعك او تكون غير حراً (عبداً) موظفاً عند السيد المتسلط مالك العبيد
المصطلح مقصود هنا لتحريك الهمة بتصوير الموقف بصورة سلبية جداً ومبالغ فيها
لم أبالغ يا استاذة ربما لم يكن لديك الوقت الكافي للمراجعة

In today's world of business, a slave with certain rights and benefits is referred to an as employee or simply just a worker. His/her worth which determines his/her salary and wages is still being derived in the same way we would that of a slave; age, knowledge, experience, health, physical strength, etc!
https://hbswk.hbs.edu/item/the-messy-link-between-slave-owne...

Corporate Slave - Corporate slaves commonly refer to the middle-class laborers who are excessively subsumed under the stifling culture of the modern-day corporate system.
https://www.academia.edu/53285256/Tales_from_the_Corporate_S...

10 signs you've become a corporate slave (and what to do ... - Ideapod
If you hate the work you do, you have choices. You can apply for other jobs, try to diversify your skills, study something in your free time. Being a corporate slave requires a sense of victimhood. Making choices based on your priorities will help you to avoid that. 4) Create stronger boundaries
https://ideapod.com/signs-of-a-corporate-slave/