This actually increases the risk.I see it as a pointless and potentially risky change. Contactless is good for relatively small transactions, but for anything over say £20 I prefer to stick the card in the slot and type my PIN in, it gives me a slightly better sense of confidence.
If you make six consecutive contactless transactions you have to re-validate your PIN. Making a chip and pin purchase resets this count. If you make additional chip and pin transactions it means there is more chance of six contactless transactions being available to be made should your card fall into the wrong hands.
That said, your bank is responsible for any loss unless you have been negligent. On the other hand you are responsible for any loss of cash from a lost or stolen wallet regardless of whether you have been negligent or not.