This might be regarded as a feature request, but I believe it's essential that Mojang makes the final decision on this matter. Currently, when riding a horse, donkey, mule, skeleton horse, zombie horse, llama, or camel, accessing your own inventory is replaced by opening the inventory of the mob you are riding. This means that rather than showcasing your skin, it showcases the skin of the entity you're mounted on. Additionally, your armor slots remain hidden, replaced by the armor slot and saddle slot or carpet slot of the mounted creature. Consequently, you're unable to view the effects affecting you as the player. It's logical to expect that the effects of the entity you're riding would be displayed instead, but this is not the current behavior. To replicate this issue, simply tame a horse, apply an effect to it using a method such as a splash potion, then ride the horse and open its inventory. You'll observe that the effect applied to the horse is not visible.