Unless you cycle across town every time you swap SIMs, I don't think this will help much. Just the fact that those two SIMs ping the same cell towers is enough for a bunch of data aggregators to correlate the numbers back to the same person.

Plus, IMEIs are often sequential, and can be queried (like a mac address) in a DB. This helps prevent theft.

So they have one IMEI, they have all for that phone.

2FA is not even remotely secure via sms, as shown 100 times over. The only reason google loves it so much, is it links your real life name to your accounts.