Two options:
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92k rows is not something fantastic, depending on row size they can all be in memory without any problems. I used PhpSpreadsheet on similar sized XLSX files on 2 Gb RAM (+2 Gb swap) virtual machine without any optimizations/streaming/chunking at all, no problems.
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PhpSpreadsheet was developed with accurate memory handling in mind and uses chunking implicitly where it can.
BTW, it's strange to ask why something IS NOT broken and works fine, usually people ask about why it IS broken :)