You’re on an ARM machine:
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= CPU =
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Processor : ARMv7 Processor rev 1 (v7l)
Valve doesn’t support ARM as far as I know, so Steam is a no-go. Slack is an Electron-based app, and according to this post there were some issues with Electron apps on ARM: https://community.endlessos.com/t/running-atom-editor-on-arm/2561/3?u=wjt but things may have changed in the meantime.