Piracy: ꜱᴀɪʟ ᴛʜᴇ ʜɪɢʜ ꜱᴇᴀꜱ

Edit: I don't pirate the mentioned software.

I'd love to use FOSS exclusively, but it's frankly impossible under certain conditions.

Acrobat is a must. Alternatives such as Evince or their back-end library can't handle the following situations:

• Formulars, such as calculating a sum based on the preceding fields.
• Field formatting, such as appending .00 to a currency amount conditionally upon field unfocus.
• Everything related to government forms due to the above.
• Large password protected PDF files.

Besides, if anything is wrong, you're on the hook for not using Acrobat.

Microsoft Office is a must.

• OnlyOffice, WPS free as in free beer, and especially LibreOffice can't handle anything beyond intermediate documents.
• OnlyOffice and WPS struggle with more advanced features, such as forms.
• LibreOffice notoriously renders Microsoft Office documents incorrectly in my experience.
• Everything in LibreOffice except LibreOffice Writer feels unpolished to me, particularly LibreOffice Calc.
• OnlyOffice supports only few fields.
• OnlyOffice permits free form input for fields that aren't.

Adobe is a must.

• Alternatives don't integrate as well with each other as Adobe apps.
• Rendering whatever you have to import that into another app is a slow workflow, compared to Adobe Premiere that embeds Adobe After Effects sequences, for example.
• Alternatives don't support scripting sometimes. Scripting is necessary to speed up slow and error-prone manual processes.
• Adobe has a rich plugin ecosystem, whereas alternatives don't support plugins at all, or don't have any notable plugins.
• Alternatives don't support Adobe file formats as well as Adobe.

You face similar problems to Adobe with alternatives, such as:

• Inconsistent keyboard shortcuts.
• Inconsistent file format support.

Overall, I'd love to, but can't. FOSS isn't good enough.