Strickland beat Izzy with the same basic recipe Weidman used to beat 38 year old Anderson.
Sound fundamentals
Forward pressure
Meticulous attention to range and defensive responsibility.
Refusal to get drawn into bait or head games
Awareness to stay balanced and not overextend.
Anderson would have had better tools to implement a "Plan B" but he may have also shared a similar stubbornness and ego that may have rendered him hesitant to do so.
Anderson struggled later in his career when the blueprint got out to be patient and avoid mistakes. He would likely have needed to adjust by utilizing one of the following:
A) drop the counter striking and "lead the dance." Anderson, especially younger Anderson had a godlike chin and he was capable of walking thru the fire, and took shots from much heavier hitters than Sean.
B) Force the clinch. Not sure how easy this would be but Anderson was lethal in the clinch and Izzy has not shown similar aptitude there.
C) Take it to the ground. IF, Anderson could get the fight to the ground he was one of the best finishers on the ground of all time. Absolutely lethal in top position, but also capable of finishing off his back if needed. Very very good in scrambles, with good enough sweeps to possibly pull guard and still get the better of the ground if all else failed.
Anderson could have overcome, but I think the people saying it would be easy are being a bit dismissive of Sean's skills and how much that particular gameplan and fighting style causes problems for counter strikers.