From ChatGPT:

If you find it hard to wash off physical (mineral) sunscreen, it’s not necessarily bad for your skin, but it might indicate that you're using a sunscreen that’s too thick or heavy for your needs. Physical sunscreens typically contain active ingredients like zinc oxide or titanium dioxide, which form a protective barrier on the skin. These ingredients can sometimes feel more resistant to removal, especially if the sunscreen is water-resistant or formulated to stay in place for extended periods.

Here’s what to consider:

1. Cleansing Effectiveness: If you’re struggling to remove the sunscreen, it might mean that you're not using the best cleansing method. Make sure you’re using a gentle but effective cleanser. Oil-based or micellar water cleansers can be helpful for breaking down the mineral sunscreen without irritating your skin. You might also need to cleanse twice—once with an oil-based cleanser and again with a regular face wash to ensure it’s fully removed.
2. Clogging Pores: If you're not properly cleansing the sunscreen off your skin, there’s a possibility that leftover residue can clog pores, especially if you wear it every day. However, this doesn’t usually happen with mineral sunscreens because they don’t penetrate the skin deeply, unlike chemical sunscreens. But for those with sensitive or acne-prone skin, build-up can still cause issues.
3. Skin Irritation: Over-scrubbing or using harsh products to remove physical sunscreen could potentially irritate the skin. If you're struggling with removal, be gentle in your approach to avoid compromising your skin’s barrier.

In summary, it's not inherently bad to have some difficulty washing off physical sunscreen, but it’s important to ensure you're using a proper cleansing routine to avoid build-up or irritation. If you're consistently having trouble removing it, you might want to try a different formula or opt for a product designed for easier removal.