We can't say we weren't warned of the Mark. Too bad some won't heed. They might save their families from Hell fire.
I struggle to believe that the mark (whatever it is) will be something that won't be obvious to true Christians. It seems clear that the mark is not just about currency exchange - but an allegiance to the beast - and any true believer that dearly loves God will have a conviction from the Holy Spirit as to what it is when it comes.
Otherwise, our salvation isn't based in faith in Christ alone - it comes down to the capability of our intellect in discerning what the mark of the beast is - and only the intelligent Christians will be saved through that time. That doesn't seem to gel with the rest of scripture as I know it.
I suspect that the mark of the best has little to do with salvation at all. It's the cart before the horse scenario. Rather - I suspect those who turn and repent - who put their faith and trust in Christ Jesus will be saved -
and as a result of their salvation they will be spared by the mark by The Holy Spirits guidance and conviction.
Likewise those who reject Christ Jesus will be the ones that continue on and receive the mark and make their allegiance with the beast and worship him - not because of lack of intelligence, but because of their state before God and rejection of Jesus Christ.
That does not contradict that those who receive the mark of the best can not be saved (Rev 20:4), nor does it contradict seeking wisdom through this. Rather - be aware of the mark and all other scriptures by all means, but don't put your fear or focus on the mark and our wisdom or intelligence as to what it is - but rather put our faith and focus on Christ Jesus - and let Him be our guiding light.