• There’s no way to meaningfully upgrade this machine anyway. The RAM is soldered, the SSD is proprietary (and 500GB already). Nothing else is upgradeable.

    Having said that, your 2015 retina MBP is still perfectly fine for basic tasks as-is; 16GB RAM, 500GB NVMe SSD, fantastic display.

    I would back up your files, nuke the OS, reinstall everything from scratch (very easy) and see how it goes.

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