Wouldn't it be easier to offer sheet?

No. 5 years x 10.2 is not worth the offersheet

Jokiharju isn't worth a 2026 1st so it's less value than an offersheet.
Also can't put the "Top 10 protection" on an offer sheet and this year's draft class looks loaded.
This also keeps those next 3 firsts available for trades that could push them over the hump if they put it all together and are contenders.

Buffalo also doesn't have their 3rd to do that. Would have to be 4 firsts.

Fair enough.

If Dallas is trading Robertson (they aren't), then they aren't accepting any kind of protection on a 1st Round Pick.

It's still a 1st that they receive after the protections so I don't think that would cause this trade to be turned away. Rather if the bit of value difference is the question they may ask for an additional midround pick to makeup for it. Buffalo already picked 9th this year so assuming they improve it's a pick in the teens that they would get in 2023 regardless of the protection.

If Buffalo wants Robertson, the deal starts with Owen Power. Otherwise feel free to pony up the offer sheet price.

I disagree.