i didn't say it is your claim, that way of thinking is a silly way that has existed before SegWit even started and it is true but not possible! basically it is an FUD that was designed to prevent SegWit activation. it is true that miners can decide to steal SegWit outputs but in order to do that they have to fork bitcoin and be on a new/different chain which the rest of the network will never follow! and also this possibility is true about all other outputs when a fork is the first step. so it is not even SegWit related.
to explain. segwit would need to be deactivated and regress the rules back to 2016 rules. thus making segwit outputs become 'anyonecanspends'
which is the worry if there was a bug. where anyone sending funds from segwit addresses could be spent by mining pools when pools add them to their block in such an event.
however if you really want to know how trusted segwits addresses are.. just look at the very guy that invented and coded segwit
(pieter wuille aka sipa)
https://bitcoin.sipa.be (bottom of website on the right).. still using legacy addressess
also even on his bitcointalk profile:
https://bitcointalk.org/index.php?action=profile;u=2786seems he is yet to trust donations on segwit addresses