Lending is risky and it's hard to trust users with their accounts as collateral for loans. Many trusted users, if trusted means green trust, with loans and they turned to be scammers.

Bitcoin is scarce and if OP already has bitcoins, keep it safely. Contribute to Bitcoin adoption does not mean you need to take risk with your bitcoin and can lose it by taking risk.

Running a Bitcoin full node, Lightning Network node, pay your purchases with bitcoins, donations in bitcoins, and more things, but I am more favorite with things I am ready to pay my bitcoin, not with taking risk and knowing that I can lose it to scammers.