The <500g parcel rate has only gone up an extra .35c, so that rate shouldn't hurt sellers who offer free postage.

Don't forget about ebays increased FVF which affects sellers with 'free' postage as they are ultimately paying FVF for the item amount + the postage component incorporated in the price

Believe it or not, many low value items only have VERY low margins so $0.35 + the additional FVF can wipe out any profit altogether.