do you really think all miners are using the exact same software..
do you really think the pools havent done their own little tweaks.. not to break the fundamental rules.. but to do other feature benefits for them locally..
No, but the greater they diverge , the more dangerous and complex it can become ... Case in Point - SPV mining. I think you are talking past each other... we are specifically referring to multiple implementations that
break the consensus rules.
Imagine what type of ecosystem we would have if were constantly in this state of mudslinging and infighting where at any given momment there were multiple implementations being lobbied
that broke consensus rules on the brink of getting support.... some at 60% threshold to activate, some at 75% , some at 95% .... this would be disastrous.
Yes , to many different developer teams...
Yes, To at least 3-4+ different implementations written in different code
Yes to varying different features , choices, wallets , ... (as long as there isn't constant politicking between versions
that break the consensus rules)