Correct, custodial wallet has no benefit from lightning rules, they should never been used for more than pocket change it whatever amount you can lose without worry. There are wallets such as Phoenix and Breeze, they are lightning nodes. There are many others, but if you want the benefit of receiving without sending first, these two offer a compromise where you can do a swap from on chain to lightning. During this swap, in that moment it is custodial. But at rest it is non custodial. Anyway the point is you can run a lightning node on your phone, no need for custodial, that is only a convenience that you are trading for complete loss of funds as a possibility.