He is MUCH better. Hanifin has been a top 20 defensive metrics player for 3 straight years. Top 5 in one of them and top 10 in another. Chychrun isn't even decent defensively. He's heavily sheltered in Ottawa even though they have no one to shelter him. Sanderson a 20 year old plays way harder minutes because Chychrun can't.
That's just not true at all. Chychrun is fine defensively and when he came over to Ottawa last year he lead the Sens in TOI% vs elite level competition. And offensively only Josi and Dougie have consistently bigger individual impacts over the last 3-4 seasons. Hanifin is a much more rounded player than Chychrun as he is a legitimate #2 but Chychrun is way better offensively and a legitimate #1 when healthy.
Hanifin's 5v5 ranking over the previous 3 years is all defensive RAPM:
20/21 - GA/60 = 52nd, SA/60 = 27th, FA/60 = 42nd, CA/60 = 28th, xGA/60 = 25th
21/22 - GA/60 = 80th, SA/60 = 46th, FA/60 = 54th, CA/60 = 29th, xGA/60 = 42nd
22/23 - GA/60 = 148th, SA/60 = 80th, FA/60 = 92nd, CA/60 = 76th, xGA/60 = 96th
Chychrun's 5v5 ranking over the previous 3 years in all defensive RAPM:
20/21 - GA/60 = 116th, SA/60 = 107th, FA/60 = 117th, CA/60 = 135th, xGA/60 = 108th
21/22 - GA/60 = 198th, SA/60 = 151st, FA/60 = 144th, CA/60 = 144th, xGA/60 = 91st
22/23 - GA/60 = 115th, SA/60 = 144th, FA/60 = 117th, CA/60 = 112th, xGA/60 = 158th
It's very important to remember that for at least 2 of those 3 seasons Hanifin played on a far better team than Chychrun as Arizona was deliberately tanking the last 2 seasons. I am not suggesting that Chychrun is better defensively than Hanifin but Chychrun is a very similar defenseman to Dougie Hamilton, one of the best defensemen for getting pucks on the net league wide and not a complete defensive liability
As for offensive impacts this is where Chychrun ranked in those 3 seasons (1st number is all strengths and 2nd number is 5v5 only)
20/21 - iSF/60 = 3rd and 8th, iFF/60 = 2nd and 3rd, iCF/60 = 4th and 5th, ixGF = 4th and 7th
21/22 - iSF/60 = 3rd and 3rd, iFF/60 = 2nd and 2nd, iCF/60 = 3rd and 2nd, ixGF = 8th and 20th
22/23 - iSF/60 = 7th and 13th, iFF/60 = 7th and 8th, iCF/60 = 7th and 15th, ixGF = 3rd and 20th