If I am a player that needs credits and observe the pricing and locations where these ores are to be sold I will simply go to trade with a 5k transport. Some locations for ores are very bad as well as end destinations.
For example look the famous Gold Ore - Molly Mine field, few k down Arranmore Base? Well, which Miner would risk to go there, to mine 5-10min and be exposed to anyone undocking from Arranmore or coming out of Omega-49 (corsair for example)? "Mining should be done in groups" - ok, so lets say we have 1 miner and 2 transports...but they will need an escort - but such a small "fleet" will put attention on the tracker and any Molly/Corsair (primary Molly) can undock, fire CD and "2mOREdai".
I am not a miner but once I was - and when I see this update I simply see no reason to consider mining as option to make credits. The "Risk" outperforms the "Gains". A 5k transport with gold ore = ~23M, delivered from Dublin to New Berlin which will take 20min mining, 20min transporting and if you get caught - sayonara. Meanwhile you can do far more than that with normal trading...which is making the Mining as last viable option. Mining should be source of income and player interaction btw pirates/miners/traders/escorts.
With these changes you wont have any miners that value their time spent online cuz again - the risk is not worth the gains.
Overall like most players stated here - this update is encouraging "single" player trading with 5k's and removing Mining as an option for lawfuls primary. Smugglers and Unlawfuls would benefit most (Again reference towards Molly Mining Field, which can undock...mine...dock...while Lawfuls will have to enter their area in order to "steal" their gold and be easy kills).
It is good to do such drastic changes but not SO drastic. If you are limiting the lawful routes at least maintain x1 ore field on lawful side as well.