All of my yard maintenance equipment have different fuel to oil ratios, anywhere from 20-50:1. My best friend that has passed was one of the best small engine repairmen in the area. He told me that all he ever used was 30:1 on everything. I'm thinking about doing the same and get rid of some of these cans. Maybe the Stihl I would keep with 50:1, any thoughts on this move.

I'm going to use 30:1 in everything and hope for the best...thanks for the input.

Strangely enough I have some stihl, several Husqvarna, few echos, robins, old toros among others. I have used stihl 50:1 only in all of them for over the last 25 years now. In my opinion all run great and I have never lost one single engine. I now use the new still oil but I liked the previous oil that cost less but is hard to find at the local store now days.

I always use too much oil. Usually around 25 to one. I have never heard of too much oil hurting anything other then fouling plugs. So I clean plugs often..

I have always mixed 32 to 1 for air cooled, and 50 to 1 for water cooled, which is the two stroke outboard motors. And I use the same oil.
Some of the more modern oils claim you use use less oil, but I do not trust them.
They will not buy me a new chainsaw if I have a problem.
My two stroke motorcycle has an oil injector pump which works fine.
I think it is Lucas oil I am using. Same stuff for the outboard motor, bike, chainsaw and weed whacker.

Used to be the folks that used OMC oil in the small outboard motors, would have them last a very long time. 20 years or more. The folks that used cheaper oil, would have problems much sooner. The OMC oil was made by Castrol, and had rust inhibitors in it. That seemed to be the difference. Motors with the cheaper oil, were getting rust during the winter months. Some would seize.

Newer Stihl saws run syn oil.
Older ones run dino mix.
Dino mix in a new saw may have a detrimental effect.

Oil to fuel doesn't matter as much as pure gas versus alcohol added. I would think your friend was right. If it did cause a problem, it would be hard to start from too much oil. Wash the spark plug and that is fixed. Just be sure to use 100% gas, without alcohol.